/*  Prototype JavaScript framework, version 1.6.0.3
 *  (c) 2005-2008 Sam Stephenson
 *
 *  Prototype is freely distributable under the terms of an MIT-style license.
 *  For details, see the Prototype web site: http://www.prototypejs.org/
 *
 *--------------------------------------------------------------------------*/

var Prototype = {
  Version: '1.6.0.3',

  Browser: {
    IE:     !!(window.attachEvent &&
        navigator.userAgent.indexOf('Opera') === -1),
        Opera:  navigator.userAgent.indexOf('Opera') > -1,
        WebKit: navigator.userAgent.indexOf('AppleWebKit/') > -1,
        Gecko:  navigator.userAgent.indexOf('Gecko') > -1 &&
            navigator.userAgent.indexOf('KHTML') === -1,
            MobileSafari: !!navigator.userAgent.match(/Apple.*Mobile.*Safari/)
  },

  BrowserFeatures: {
    XPath: !!document.evaluate,
    SelectorsAPI: !!document.querySelector,
    ElementExtensions: !!window.HTMLElement,
    SpecificElementExtensions:
        document.createElement('div')['__proto__'] &&
        document.createElement('div')['__proto__'] !==
        document.createElement('form')['__proto__']
  },

  ScriptFragment: '<script[^>]*>([\\S\\s]*?)<\/script>',
  JSONFilter: /^\/\*-secure-([\s\S]*)\*\/\s*$/,

  emptyFunction: function() { },
  K: function(x) { return x }
};

if (Prototype.Browser.MobileSafari)
  Prototype.BrowserFeatures.SpecificElementExtensions = false;


/* Based on Alex Arnell's inheritance implementation. */
var Class = {
  create: function() {
    var parent = null, properties = $A(arguments);
    if (Object.isFunction(properties[0]))
    parent = properties.shift();

    function klass() {
      this.initialize.apply(this, arguments);
    }

    Object.extend(klass, Class.Methods);
    klass.superclass = parent;
    klass.subclasses = [];

    if (parent) {
      var subclass = function() { };
      subclass.prototype = parent.prototype;
      klass.prototype = new subclass;
      parent.subclasses.push(klass);
    }

    for (var i = 0; i < properties.length; i++)
    klass.addMethods(properties[i]);

    if (!klass.prototype.initialize)
    klass.prototype.initialize = Prototype.emptyFunction;

    klass.prototype.constructor = klass;

    return klass;
  }
};

Class.Methods = {
  addMethods: function(source) {
    var ancestor   = this.superclass && this.superclass.prototype;
    var properties = Object.keys(source);

    if (!Object.keys({ toString: true }).length)
    properties.push("toString", "valueOf");

    for (var i = 0, length = properties.length; i < length; i++) {
      var property = properties[i], value = source[property];
      if (ancestor && Object.isFunction(value) &&
      value.argumentNames().first() == "$super") {
        var method = value;
        value = (function(m) {
          return function() { return ancestor[m].apply(this, arguments) };
        })(property).wrap(method);

        value.valueOf = method.valueOf.bind(method);
        value.toString = method.toString.bind(method);
      }
      this.prototype[property] = value;
    }

    return this;
  }
};

var Abstract = { };

Object.extend = function(destination, source) {
  for (var property in source)
  destination[property] = source[property];
  return destination;
};

Object.extend(Object, {
  inspect: function(object) {
    try {
      if (Object.isUndefined(object)) return 'undefined';
      if (object === null) return 'null';
      return object.inspect ? object.inspect() : String(object);
    } catch (e) {
      if (e instanceof RangeError) return '...';
      throw e;
    }
  },

  toJSON: function(object) {
    var type = typeof object;
    switch (type) {
      case 'undefined':
      case 'function':
          case 'unknown': return;
      case 'boolean': return object.toString();
    }

    if (object === null) return 'null';
    if (object.toJSON) return object.toJSON();
    if (Object.isElement(object)) return;

    var results = [];
    for (var property in object) {
      var value = Object.toJSON(object[property]);
      if (!Object.isUndefined(value))
      results.push(property.toJSON() + ': ' + value);
    }

    return '{' + results.join(', ') + '}';
  },

  toQueryString: function(object) {
    return $H(object).toQueryString();
  },

  toHTML: function(object) {
    return object && object.toHTML ? object.toHTML() : String.interpret(object);
  },

  keys: function(object) {
    var keys = [];
    for (var property in object)
    keys.push(property);
    return keys;
  },

  values: function(object) {
    var values = [];
    for (var property in object)
    values.push(object[property]);
    return values;
  },

  clone: function(object) {
    return Object.extend({ }, object);
  },

  isElement: function(object) {
    return !!(object && object.nodeType == 1);
  },

  isArray: function(object) {
    return object != null && typeof object == "object" &&
        'splice' in object && 'join' in object;
  },

  isHash: function(object) {
    return object instanceof Hash;
  },

  isFunction: function(object) {
    return typeof object == "function";
  },

  isString: function(object) {
    return typeof object == "string";
  },

  isNumber: function(object) {
    return typeof object == "number";
  },

  isUndefined: function(object) {
    return typeof object == "undefined";
  }
});

Object.extend(Function.prototype, {
  argumentNames: function() {
    var names = this.toString().match(/^[\s\(]*function[^(]*\(([^\)]*)\)/)[1]
        .replace(/\s+/g, '').split(',');
    return names.length == 1 && !names[0] ? [] : names;
  },

  bind: function() {
    if (arguments.length < 2 && Object.isUndefined(arguments[0])) return this;
    var __method = this, args = $A(arguments), object = args.shift();
    return function() {
      return __method.apply(object, args.concat($A(arguments)));
    }
  },

  bindAsEventListener: function() {
    var __method = this, args = $A(arguments), object = args.shift();
    return function(event) {
      return __method.apply(object, [event || window.event].concat(args));
    }
  },

  curry: function() {
    if (!arguments.length) return this;
    var __method = this, args = $A(arguments);
    return function() {
      return __method.apply(this, args.concat($A(arguments)));
    }
  },

  delay: function() {
    var __method = this, args = $A(arguments), timeout = args.shift() * 1000;
    return window.setTimeout(function() {
      return __method.apply(__method, args);
    }, timeout);
  },

  defer: function() {
    var args = [0.01].concat($A(arguments));
    return this.delay.apply(this, args);
  },

  wrap: function(wrapper) {
    var __method = this;
    return function() {
      return wrapper.apply(this, [__method.bind(this)].concat($A(arguments)));
    }
  },

  methodize: function() {
    if (this._methodized) return this._methodized;
    var __method = this;
    return this._methodized = function() {
      return __method.apply(null, [this].concat($A(arguments)));
    };
  }
});

Date.prototype.toJSON = function() {
  return '"' + this.getUTCFullYear() + '-' +
      (this.getUTCMonth() + 1).toPaddedString(2) + '-' +
      this.getUTCDate().toPaddedString(2) + 'T' +
      this.getUTCHours().toPaddedString(2) + ':' +
      this.getUTCMinutes().toPaddedString(2) + ':' +
      this.getUTCSeconds().toPaddedString(2) + 'Z"';
};

var Try = {
  these: function() {
    var returnValue;

    for (var i = 0, length = arguments.length; i < length; i++) {
      var lambda = arguments[i];
      try {
        returnValue = lambda();
        break;
      } catch (e) { }
    }

    return returnValue;
  }
};

RegExp.prototype.match = RegExp.prototype.test;

RegExp.escape = function(str) {
  return String(str).replace(/([.*+?^=!:${}()|[\]\/\\])/g, '\\$1');
};

  /*--------------------------------------------------------------------------*/

      var PeriodicalExecuter = Class.create({
    initialize: function(callback, frequency) {
    this.callback = callback;
  this.frequency = frequency;
  this.currentlyExecuting = false;

  this.registerCallback();
},

  registerCallback: function() {
    this.timer = setInterval(this.onTimerEvent.bind(this), this.frequency * 1000);
},

  execute: function() {
    this.callback(this);
},

  stop: function() {
    if (!this.timer) return;
  clearInterval(this.timer);
  this.timer = null;
},

  onTimerEvent: function() {
    if (!this.currentlyExecuting) {
    try {
    this.currentlyExecuting = true;
  this.execute();
} finally {
    this.currentlyExecuting = false;
}
}
}
});
  Object.extend(String, {
    interpret: function(value) {
    return value == null ? '' : String(value);
},
  specialChar: {
    '\b': '\\b',
    '\t': '\\t',
    '\n': '\\n',
    '\f': '\\f',
    '\r': '\\r',
    '\\': '\\\\'
}
});

  Object.extend(String.prototype, {
    gsub: function(pattern, replacement) {
    var result = '', source = this, match;
  replacement = arguments.callee.prepareReplacement(replacement);

  while (source.length > 0) {
    if (match = source.match(pattern)) {
    result += source.slice(0, match.index);
  result += String.interpret(replacement(match));
  source  = source.slice(match.index + match[0].length);
} else {
    result += source, source = '';
}
}
  return result;
},

  sub: function(pattern, replacement, count) {
    replacement = this.gsub.prepareReplacement(replacement);
  count = Object.isUndefined(count) ? 1 : count;

  return this.gsub(pattern, function(match) {
    if (--count < 0) return match[0];
  return replacement(match);
});
},

  scan: function(pattern, iterator) {
    this.gsub(pattern, iterator);
  return String(this);
},

  truncate: function(length, truncation) {
    length = length || 30;
  truncation = Object.isUndefined(truncation) ? '...' : truncation;
  return this.length > length ?
      this.slice(0, length - truncation.length) + truncation : String(this);
},

  strip: function() {
    return this.replace(/^\s+/, '').replace(/\s+$/, '');
},

  stripTags: function() {
    return this.replace(/<\/?[^>]+>/gi, '');
  },

  stripScripts: function() {
    return this.replace(new RegExp(Prototype.ScriptFragment, 'img'), '');
  },

  extractScripts: function() {
    var matchAll = new RegExp(Prototype.ScriptFragment, 'img');
    var matchOne = new RegExp(Prototype.ScriptFragment, 'im');
    return (this.match(matchAll) || []).map(function(scriptTag) {
      return (scriptTag.match(matchOne) || ['', ''])[1];
    });
  },

  evalScripts: function() {
    return this.extractScripts().map(function(script) { return eval(script) });
  },

  escapeHTML: function() {
    var self = arguments.callee;
    self.text.data = this;
    return self.div.innerHTML;
  },

  unescapeHTML: function() {
    var div = new Element('div');
    div.innerHTML = this.stripTags();
    return div.childNodes[0] ? (div.childNodes.length > 1 ?
      $A(div.childNodes).inject('', function(memo, node) { return memo+node.nodeValue }) :
        div.childNodes[0].nodeValue) : '';
  },

  toQueryParams: function(separator) {
    var match = this.strip().match(/([^?#]*)(#.*)?$/);
    if (!match) return { };

    return match[1].split(separator || '&').inject({ }, function(hash, pair) {
      if ((pair = pair.split('='))[0]) {
        var key = decodeURIComponent(pair.shift());
        var value = pair.length > 1 ? pair.join('=') : pair[0];
        if (value != undefined) value = decodeURIComponent(value);

        if (key in hash) {
          if (!Object.isArray(hash[key])) hash[key] = [hash[key]];
          hash[key].push(value);
        }
        else hash[key] = value;
      }
      return hash;
    });
  },

  toArray: function() {
    return this.split('');
  },

  succ: function() {
    return this.slice(0, this.length - 1) +
        String.fromCharCode(this.charCodeAt(this.length - 1) + 1);
  },

  times: function(count) {
    return count < 1 ? '' : new Array(count + 1).join(this);
  },

  camelize: function() {
    var parts = this.split('-'), len = parts.length;
    if (len == 1) return parts[0];

    var camelized = this.charAt(0) == '-'
        ? parts[0].charAt(0).toUpperCase() + parts[0].substring(1)
      : parts[0];

    for (var i = 1; i < len; i++)
    camelized += parts[i].charAt(0).toUpperCase() + parts[i].substring(1);

    return camelized;
  },

  capitalize: function() {
    return this.charAt(0).toUpperCase() + this.substring(1).toLowerCase();
  },

  underscore: function() {
    return this.gsub(/::/, '/').gsub(/([A-Z]+)([A-Z][a-z])/,'#{1}_#{2}').gsub(/([a-z\d])([A-Z])/,'#{1}_#{2}').gsub(/-/,'_').toLowerCase();
  },

  dasherize: function() {
    return this.gsub(/_/,'-');
  },

  inspect: function(useDoubleQuotes) {
    var escapedString = this.gsub(/[\x00-\x1f\\]/, function(match) {
      var character = String.specialChar[match[0]];
    return character ? character : '\\u00' + match[0].charCodeAt().toPaddedString(2, 16);
  });
    if (useDoubleQuotes) return '"' + escapedString.replace(/"/g, '\\"') + '"';
    return "'" + escapedString.replace(/'/g, '\\\'') + "'";
  },

  toJSON: function() {
    return this.inspect(true);
  },

  unfilterJSON: function(filter) {
    return this.sub(filter || Prototype.JSONFilter, '#{1}');
  },

  isJSON: function() {
    var str = this;
    if (str.blank()) return false;
    str = this.replace(/\\./g, '@').replace(/"[^"\\\n\r]*"/g, '');
    return (/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(str);
  },

  evalJSON: function(sanitize) {
    var json = this.unfilterJSON();
    try {
      if (!sanitize || json.isJSON()) return eval('(' + json + ')');
    } catch (e) { }
    throw new SyntaxError('Badly formed JSON string: ' + this.inspect());
  },

  include: function(pattern) {
    return this.indexOf(pattern) > -1;
  },

  startsWith: function(pattern) {
    return this.indexOf(pattern) === 0;
  },

  endsWith: function(pattern) {
    var d = this.length - pattern.length;
    return d >= 0 && this.lastIndexOf(pattern) === d;
  },

  empty: function() {
    return this == '';
  },

  blank: function() {
    return /^\s*$/.test(this);
  },

  interpolate: function(object, pattern) {
    return new Template(this, pattern).evaluate(object);
  }
});

if (Prototype.Browser.WebKit || Prototype.Browser.IE) Object.extend(String.prototype, {
  escapeHTML: function() {
    return this.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;');
  },
  unescapeHTML: function() {
    return this.stripTags().replace(/&amp;/g,'&').replace(/&lt;/g,'<').replace(/&gt;/g,'>');
  }
});

String.prototype.gsub.prepareReplacement = function(replacement) {
  if (Object.isFunction(replacement)) return replacement;
  var template = new Template(replacement);
  return function(match) { return template.evaluate(match) };
};

String.prototype.parseQuery = String.prototype.toQueryParams;

Object.extend(String.prototype.escapeHTML, {
  div:  document.createElement('div'),
  text: document.createTextNode('')
});

String.prototype.escapeHTML.div.appendChild(String.prototype.escapeHTML.text);

var Template = Class.create({
  initialize: function(template, pattern) {
    this.template = template.toString();
    this.pattern = pattern || Template.Pattern;
  },

  evaluate: function(object) {
    if (Object.isFunction(object.toTemplateReplacements))
    object = object.toTemplateReplacements();

    return this.template.gsub(this.pattern, function(match) {
      if (object == null) return '';

      var before = match[1] || '';
      if (before == '\\') return match[2];

      var ctx = object, expr = match[3];
      var pattern = /^([^.[]+|\[((?:.*?[^\\])?)\])(\.|\[|$)/;
      match = pattern.exec(expr);
      if (match == null) return before;

      while (match != null) {
        var comp = match[1].startsWith('[') ? match[2].gsub('\\\\]', ']') : match[1];
      ctx = ctx[comp];
      if (null == ctx || '' == match[3]) break;
      expr = expr.substring('[' == match[3] ? match[1].length : match[0].length);
      match = pattern.exec(expr);
    }

      return before + String.interpret(ctx);
    });
    }
    });
      Template.Pattern = /(^|.|\r|\n)(#\{(.*?)\})/;

      var $break = { };

      var Enumerable = {
        each: function(iterator, context) {
          var index = 0;
          try {
            this._each(function(value) {
              iterator.call(context, value, index++);
            });
          } catch (e) {
            if (e != $break) throw e;
          }
          return this;
        },

        eachSlice: function(number, iterator, context) {
          var index = -number, slices = [], array = this.toArray();
          if (number < 1) return array;
          while ((index += number) < array.length)
          slices.push(array.slice(index, index+number));
          return slices.collect(iterator, context);
        },

        all: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var result = true;
          this.each(function(value, index) {
            result = result && !!iterator.call(context, value, index);
            if (!result) throw $break;
          });
          return result;
        },

        any: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var result = false;
          this.each(function(value, index) {
            if (result = !!iterator.call(context, value, index))
            throw $break;
          });
          return result;
        },

        collect: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var results = [];
          this.each(function(value, index) {
            results.push(iterator.call(context, value, index));
          });
          return results;
        },

        detect: function(iterator, context) {
          var result;
          this.each(function(value, index) {
            if (iterator.call(context, value, index)) {
              result = value;
              throw $break;
            }
          });
          return result;
        },

        findAll: function(iterator, context) {
          var results = [];
          this.each(function(value, index) {
            if (iterator.call(context, value, index))
            results.push(value);
          });
          return results;
        },

        grep: function(filter, iterator, context) {
          iterator = iterator || Prototype.K;
          var results = [];

          if (Object.isString(filter))
          filter = new RegExp(filter);

          this.each(function(value, index) {
            if (filter.match(value))
            results.push(iterator.call(context, value, index));
          });
          return results;
        },

        include: function(object) {
          if (Object.isFunction(this.indexOf))
          if (this.indexOf(object) != -1) return true;

          var found = false;
          this.each(function(value) {
            if (value == object) {
              found = true;
              throw $break;
            }
          });
          return found;
        },

        inGroupsOf: function(number, fillWith) {
          fillWith = Object.isUndefined(fillWith) ? null : fillWith;
          return this.eachSlice(number, function(slice) {
            while(slice.length < number) slice.push(fillWith);
            return slice;
          });
        },

        inject: function(memo, iterator, context) {
          this.each(function(value, index) {
            memo = iterator.call(context, memo, value, index);
          });
          return memo;
        },

        invoke: function(method) {
          var args = $A(arguments).slice(1);
          return this.map(function(value) {
            return value[method].apply(value, args);
          });
        },

        max: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var result;
          this.each(function(value, index) {
            value = iterator.call(context, value, index);
            if (result == null || value >= result)
            result = value;
          });
          return result;
        },

        min: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var result;
          this.each(function(value, index) {
            value = iterator.call(context, value, index);
            if (result == null || value < result)
            result = value;
          });
          return result;
        },

        partition: function(iterator, context) {
          iterator = iterator || Prototype.K;
          var trues = [], falses = [];
          this.each(function(value, index) {
            (iterator.call(context, value, index) ?
                trues : falses).push(value);
          });
          return [trues, falses];
        },

        pluck: function(property) {
          var results = [];
          this.each(function(value) {
            results.push(value[property]);
          });
          return results;
        },

        reject: function(iterator, context) {
          var results = [];
          this.each(function(value, index) {
            if (!iterator.call(context, value, index))
            results.push(value);
          });
          return results;
        },

        sortBy: function(iterator, context) {
          return this.map(function(value, index) {
            return {
              value: value,
              criteria: iterator.call(context, value, index)
            };
          }).sort(function(left, right) {
            var a = left.criteria, b = right.criteria;
            return a < b ? -1 : a > b ? 1 : 0;
          }).pluck('value');
        },

        toArray: function() {
          return this.map();
        },

        zip: function() {
          var iterator = Prototype.K, args = $A(arguments);
          if (Object.isFunction(args.last()))
          iterator = args.pop();

          var collections = [this].concat(args).map($A);
          return this.map(function(value, index) {
            return iterator(collections.pluck(index));
          });
        },

        size: function() {
          return this.toArray().length;
        },

        inspect: function() {
          return '#<Enumerable:' + this.toArray().inspect() + '>';
        }
      };

      Object.extend(Enumerable, {
        map:     Enumerable.collect,
        find:    Enumerable.detect,
        select:  Enumerable.findAll,
        filter:  Enumerable.findAll,
        member:  Enumerable.include,
        entries: Enumerable.toArray,
        every:   Enumerable.all,
        some:    Enumerable.any
      });
      function $A(iterable) {
        if (!iterable) return [];
        if (iterable.toArray) return iterable.toArray();
        var length = iterable.length || 0, results = new Array(length);
        while (length--) results[length] = iterable[length];
        return results;
      }

      if (Prototype.Browser.WebKit) {
        $A = function(iterable) {
          if (!iterable) return [];
    // In Safari, only use the `toArray` method if it's not a NodeList.
    // A NodeList is a function, has an function `item` property, and a numeric
    // `length` property. Adapted from Google Doctype.
          if (!(typeof iterable === 'function' && typeof iterable.length ===
          'number' && typeof iterable.item === 'function') && iterable.toArray)
          return iterable.toArray();
          var length = iterable.length || 0, results = new Array(length);
          while (length--) results[length] = iterable[length];
          return results;
        };
      }

      Array.from = $A;

      Object.extend(Array.prototype, Enumerable);

      if (!Array.prototype._reverse) Array.prototype._reverse = Array.prototype.reverse;

      Object.extend(Array.prototype, {
        _each: function(iterator) {
          for (var i = 0, length = this.length; i < length; i++)
          iterator(this[i]);
        },

        clear: function() {
          this.length = 0;
          return this;
        },

        first: function() {
          return this[0];
        },

        last: function() {
          return this[this.length - 1];
        },

        compact: function() {
          return this.select(function(value) {
            return value != null;
          });
        },

        flatten: function() {
          return this.inject([], function(array, value) {
            return array.concat(Object.isArray(value) ?
                value.flatten() : [value]);
          });
        },

        without: function() {
          var values = $A(arguments);
          return this.select(function(value) {
            return !values.include(value);
          });
        },

        reverse: function(inline) {
          return (inline !== false ? this : this.toArray())._reverse();
        },

        reduce: function() {
          return this.length > 1 ? this : this[0];
        },

        uniq: function(sorted) {
          return this.inject([], function(array, value, index) {
            if (0 == index || (sorted ? array.last() != value : !array.include(value)))
            array.push(value);
            return array;
          });
        },

        intersect: function(array) {
          return this.uniq().findAll(function(item) {
            return array.detect(function(value) { return item === value });
          });
        },

        clone: function() {
          return [].concat(this);
        },

        size: function() {
          return this.length;
        },

        inspect: function() {
          return '[' + this.map(Object.inspect).join(', ') + ']';
        },

        toJSON: function() {
          var results = [];
          this.each(function(object) {
            var value = Object.toJSON(object);
            if (!Object.isUndefined(value)) results.push(value);
          });
          return '[' + results.join(', ') + ']';
        }
      });

// use native browser JS 1.6 implementation if available
      if (Object.isFunction(Array.prototype.forEach))
      Array.prototype._each = Array.prototype.forEach;

      if (!Array.prototype.indexOf) Array.prototype.indexOf = function(item, i) {
        i || (i = 0);
        var length = this.length;
        if (i < 0) i = length + i;
        for (; i < length; i++)
        if (this[i] === item) return i;
        return -1;
      };

      if (!Array.prototype.lastIndexOf) Array.prototype.lastIndexOf = function(item, i) {
        i = isNaN(i) ? this.length : (i < 0 ? this.length + i : i) + 1;
        var n = this.slice(0, i).reverse().indexOf(item);
        return (n < 0) ? n : i - n - 1;
      };

      Array.prototype.toArray = Array.prototype.clone;

      function $w(string) {
        if (!Object.isString(string)) return [];
        string = string.strip();
        return string ? string.split(/\s+/) : [];
      }

      if (Prototype.Browser.Opera){
        Array.prototype.concat = function() {
          var array = [];
          for (var i = 0, length = this.length; i < length; i++) array.push(this[i]);
          for (var i = 0, length = arguments.length; i < length; i++) {
            if (Object.isArray(arguments[i])) {
              for (var j = 0, arrayLength = arguments[i].length; j < arrayLength; j++)
              array.push(arguments[i][j]);
            } else {
              array.push(arguments[i]);
            }
          }
          return array;
        };
      }
      Object.extend(Number.prototype, {
        toColorPart: function() {
          return this.toPaddedString(2, 16);
        },

        succ: function() {
          return this + 1;
        },

        times: function(iterator, context) {
          $R(0, this, true).each(iterator, context);
          return this;
        },

        toPaddedString: function(length, radix) {
          var string = this.toString(radix || 10);
          return '0'.times(length - string.length) + string;
        },

        toJSON: function() {
          return isFinite(this) ? this.toString() : 'null';
        }
      });

      $w('abs round ceil floor').each(function(method){
        Number.prototype[method] = Math[method].methodize();
      });
      function $H(object) {
        return new Hash(object);
      };

      var Hash = Class.create(Enumerable, (function() {

        function toQueryPair(key, value) {
          if (Object.isUndefined(value)) return key;
          return key + '=' + encodeURIComponent(String.interpret(value));
        }

        return {
          initialize: function(object) {
            this._object = Object.isHash(object) ? object.toObject() : Object.clone(object);
          },

          _each: function(iterator) {
            for (var key in this._object) {
              var value = this._object[key], pair = [key, value];
              pair.key = key;
              pair.value = value;
              iterator(pair);
            }
          },

          set: function(key, value) {
            return this._object[key] = value;
          },

          get: function(key) {
      // simulating poorly supported hasOwnProperty
            if (this._object[key] !== Object.prototype[key])
            return this._object[key];
          },

          unset: function(key) {
            var value = this._object[key];
            delete this._object[key];
            return value;
          },

          toObject: function() {
            return Object.clone(this._object);
          },

          keys: function() {
            return this.pluck('key');
          },

          values: function() {
            return this.pluck('value');
          },

          index: function(value) {
            var match = this.detect(function(pair) {
              return pair.value === value;
            });
            return match && match.key;
          },

          merge: function(object) {
            return this.clone().update(object);
          },

          update: function(object) {
            return new Hash(object).inject(this, function(result, pair) {
              result.set(pair.key, pair.value);
              return result;
            });
          },

          toQueryString: function() {
            return this.inject([], function(results, pair) {
              var key = encodeURIComponent(pair.key), values = pair.value;

              if (values && typeof values == 'object') {
                if (Object.isArray(values))
                return results.concat(values.map(toQueryPair.curry(key)));
              } else results.push(toQueryPair(key, values));
              return results;
            }).join('&');
          },

          inspect: function() {
            return '#<Hash:{' + this.map(function(pair) {
              return pair.map(Object.inspect).join(': ');
            }).join(', ') + '}>';
          },

          toJSON: function() {
            return Object.toJSON(this.toObject());
          },

          clone: function() {
            return new Hash(this);
          }
        }
      })());

      Hash.prototype.toTemplateReplacements = Hash.prototype.toObject;
      Hash.from = $H;
      var ObjectRange = Class.create(Enumerable, {
        initialize: function(start, end, exclusive) {
          this.start = start;
          this.end = end;
          this.exclusive = exclusive;
        },

        _each: function(iterator) {
          var value = this.start;
          while (this.include(value)) {
            iterator(value);
            value = value.succ();
          }
        },

        include: function(value) {
          if (value < this.start)
          return false;
          if (this.exclusive)
          return value < this.end;
          return value <= this.end;
        }
      });

      var $R = function(start, end, exclusive) {
        return new ObjectRange(start, end, exclusive);
      };

      var Ajax = {
        getTransport: function() {
          return Try.these(
          function() {return new XMLHttpRequest()},
          function() {return new ActiveXObject('Msxml2.XMLHTTP')},
          function() {return new ActiveXObject('Microsoft.XMLHTTP')}
    ) || false;
        },

        activeRequestCount: 0
      };

      Ajax.Responders = {
        responders: [],

        _each: function(iterator) {
          this.responders._each(iterator);
        },

        register: function(responder) {
          if (!this.include(responder))
          this.responders.push(responder);
        },

        unregister: function(responder) {
          this.responders = this.responders.without(responder);
        },

        dispatch: function(callback, request, transport, json) {
          this.each(function(responder) {
            if (Object.isFunction(responder[callback])) {
              try {
                responder[callback].apply(responder, [request, transport, json]);
              } catch (e) { }
            }
          });
        }
      };

      Object.extend(Ajax.Responders, Enumerable);

      Ajax.Responders.register({
        onCreate:   function() { Ajax.activeRequestCount++ },
        onComplete: function() { Ajax.activeRequestCount-- }
      });

      Ajax.Base = Class.create({
        initialize: function(options) {
          this.options = {
            method:       'post',
            asynchronous: true,
            contentType:  'application/x-www-form-urlencoded',
            encoding:     'UTF-8',
            parameters:   '',
            evalJSON:     true,
            evalJS:       true
          };
          Object.extend(this.options, options || { });

          this.options.method = this.options.method.toLowerCase();

          if (Object.isString(this.options.parameters))
          this.options.parameters = this.options.parameters.toQueryParams();
          else if (Object.isHash(this.options.parameters))
          this.options.parameters = this.options.parameters.toObject();
        }
      });

      Ajax.Request = Class.create(Ajax.Base, {
        _complete: false,

        initialize: function($super, url, options) {
          $super(options);
          this.transport = Ajax.getTransport();
          this.request(url);
        },

        request: function(url) {
          this.url = url;
          this.method = this.options.method;
          var params = Object.clone(this.options.parameters);

          if (!['get', 'post'].include(this.method)) {
      // simulate other verbs over post
            params['_method'] = this.method;
            this.method = 'post';
          }

          this.parameters = params;

          if (params = Object.toQueryString(params)) {
      // when GET, append parameters to URL
            if (this.method == 'get')
            this.url += (this.url.include('?') ? '&' : '?') + params;
            else if (/Konqueror|Safari|KHTML/.test(navigator.userAgent))
            params += '&_=';
          }

          try {
            var response = new Ajax.Response(this);
            if (this.options.onCreate) this.options.onCreate(response);
            Ajax.Responders.dispatch('onCreate', this, response);

            this.transport.open(this.method.toUpperCase(), this.url,
            this.options.asynchronous);

            if (this.options.asynchronous) this.respondToReadyState.bind(this).defer(1);

            this.transport.onreadystatechange = this.onStateChange.bind(this);
            this.setRequestHeaders();

            this.body = this.method == 'post' ? (this.options.postBody || params) : null;
            this.transport.send(this.body);

            /* Force Firefox to handle ready state 4 for synchronous requests */
            if (!this.options.asynchronous && this.transport.overrideMimeType)
            this.onStateChange();

          }
          catch (e) {
            this.dispatchException(e);
          }
        },

        onStateChange: function() {
          var readyState = this.transport.readyState;
          if (readyState > 1 && !((readyState == 4) && this._complete))
          this.respondToReadyState(this.transport.readyState);
        },

        setRequestHeaders: function() {
          var headers = {
            'X-Requested-With': 'XMLHttpRequest',
            'X-Prototype-Version': Prototype.Version,
            'Accept': 'text/javascript, text/html, application/xml, text/xml, */*'
          };

          if (this.method == 'post') {
            headers['Content-type'] = this.options.contentType +
                (this.options.encoding ? '; charset=' + this.options.encoding : '');

      /* Force "Connection: close" for older Mozilla browsers to work
            * around a bug where XMLHttpRequest sends an incorrect
            * Content-length header. See Mozilla Bugzilla #246651.
      */
            if (this.transport.overrideMimeType &&
            (navigator.userAgent.match(/Gecko\/(\d{4})/) || [0,2005])[1] < 2005)
            headers['Connection'] = 'close';
          }

    // user-defined headers
          if (typeof this.options.requestHeaders == 'object') {
            var extras = this.options.requestHeaders;

            if (Object.isFunction(extras.push))
            for (var i = 0, length = extras.length; i < length; i += 2)
            headers[extras[i]] = extras[i+1];
            else
              $H(extras).each(function(pair) { headers[pair.key] = pair.value });
          }

          for (var name in headers)
          this.transport.setRequestHeader(name, headers[name]);
        },

        success: function() {
          var status = this.getStatus();
          return !status || (status >= 200 && status < 300);
        },

        getStatus: function() {
          try {
            return this.transport.status || 0;
          } catch (e) { return 0 }
        },

        respondToReadyState: function(readyState) {
          var state = Ajax.Request.Events[readyState], response = new Ajax.Response(this);

          if (state == 'Complete') {
            try {
              this._complete = true;
              (this.options['on' + response.status]
                  || this.options['on' + (this.success() ? 'Success' : 'Failure')]
                  || Prototype.emptyFunction)(response, response.headerJSON);
            } catch (e) {
              this.dispatchException(e);
            }

            var contentType = response.getHeader('Content-type');
            if (this.options.evalJS == 'force'
            || (this.options.evalJS && this.isSameOrigin() && contentType
            && contentType.match(/^\s*(text|application)\/(x-)?(java|ecma)script(;.*)?\s*$/i)))
            this.evalResponse();
          }

          try {
            (this.options['on' + state] || Prototype.emptyFunction)(response, response.headerJSON);
            Ajax.Responders.dispatch('on' + state, this, response, response.headerJSON);
          } catch (e) {
            this.dispatchException(e);
          }

          if (state == 'Complete') {
      // avoid memory leak in MSIE: clean up
            this.transport.onreadystatechange = Prototype.emptyFunction;
          }
        },

        isSameOrigin: function() {
          var m = this.url.match(/^\s*https?:\/\/[^\/]*/);
          return !m || (m[0] == '#{protocol}//#{domain}#{port}'.interpolate({
            protocol: location.protocol,
            domain: document.domain,
            port: location.port ? ':' + location.port : ''
          }));
        },

        getHeader: function(name) {
          try {
            return this.transport.getResponseHeader(name) || null;
          } catch (e) { return null }
        },

        evalResponse: function() {
          try {
            return eval((this.transport.responseText || '').unfilterJSON());
          } catch (e) {
            this.dispatchException(e);
          }
        },

        dispatchException: function(exception) {
          (this.options.onException || Prototype.emptyFunction)(this, exception);
          Ajax.Responders.dispatch('onException', this, exception);
        }
      });

      Ajax.Request.Events =
          ['Uninitialized', 'Loading', 'Loaded', 'Interactive', 'Complete'];

      Ajax.Response = Class.create({
        initialize: function(request){
          this.request = request;
          var transport  = this.transport  = request.transport,
          readyState = this.readyState = transport.readyState;

          if((readyState > 2 && !Prototype.Browser.IE) || readyState == 4) {
            this.status       = this.getStatus();
            this.statusText   = this.getStatusText();
            this.responseText = String.interpret(transport.responseText);
            this.headerJSON   = this._getHeaderJSON();
          }

          if(readyState == 4) {
            var xml = transport.responseXML;
            this.responseXML  = Object.isUndefined(xml) ? null : xml;
            this.responseJSON = this._getResponseJSON();
          }
        },

        status:      0,
        statusText: '',

        getStatus: Ajax.Request.prototype.getStatus,

        getStatusText: function() {
          try {
            return this.transport.statusText || '';
          } catch (e) { return '' }
        },

        getHeader: Ajax.Request.prototype.getHeader,

        getAllHeaders: function() {
          try {
            return this.getAllResponseHeaders();
          } catch (e) { return null }
        },

        getResponseHeader: function(name) {
          return this.transport.getResponseHeader(name);
        },

        getAllResponseHeaders: function() {
          return this.transport.getAllResponseHeaders();
        },

        _getHeaderJSON: function() {
          var json = this.getHeader('X-JSON');
          if (!json) return null;
          json = decodeURIComponent(escape(json));
          try {
            return json.evalJSON(this.request.options.sanitizeJSON ||
                !this.request.isSameOrigin());
          } catch (e) {
            this.request.dispatchException(e);
          }
        },

        _getResponseJSON: function() {
          var options = this.request.options;
          if (!options.evalJSON || (options.evalJSON != 'force' &&
          !(this.getHeader('Content-type') || '').include('application/json')) ||
          this.responseText.blank())
          return null;
          try {
            return this.responseText.evalJSON(options.sanitizeJSON ||
                !this.request.isSameOrigin());
          } catch (e) {
            this.request.dispatchException(e);
          }
        }
      });

      Ajax.Updater = Class.create(Ajax.Request, {
        initialize: function($super, container, url, options) {
          this.container = {
            success: (container.success || container),
            failure: (container.failure || (container.success ? null : container))
          };

          options = Object.clone(options);
          var onComplete = options.onComplete;
          options.onComplete = (function(response, json) {
            this.updateContent(response.responseText);
            if (Object.isFunction(onComplete)) onComplete(response, json);
          }).bind(this);

          $super(url, options);
        },

        updateContent: function(responseText) {
          var receiver = this.container[this.success() ? 'success' : 'failure'],
          options = this.options;

          if (!options.evalScripts) responseText = responseText.stripScripts();

          if (receiver = $(receiver)) {
            if (options.insertion) {
              if (Object.isString(options.insertion)) {
                var insertion = { }; insertion[options.insertion] = responseText;
                receiver.insert(insertion);
              }
              else options.insertion(receiver, responseText);
            }
            else receiver.update(responseText);
          }
        }
      });

      Ajax.PeriodicalUpdater = Class.create(Ajax.Base, {
        initialize: function($super, container, url, options) {
          $super(options);
          this.onComplete = this.options.onComplete;

          this.frequency = (this.options.frequency || 2);
          this.decay = (this.options.decay || 1);

          this.updater = { };
          this.container = container;
          this.url = url;

          this.start();
        },

        start: function() {
          this.options.onComplete = this.updateComplete.bind(this);
          this.onTimerEvent();
        },

        stop: function() {
          this.updater.options.onComplete = undefined;
          clearTimeout(this.timer);
          (this.onComplete || Prototype.emptyFunction).apply(this, arguments);
        },

        updateComplete: function(response) {
          if (this.options.decay) {
            this.decay = (response.responseText == this.lastText ?
                this.decay * this.options.decay : 1);

            this.lastText = response.responseText;
          }
          this.timer = this.onTimerEvent.bind(this).delay(this.decay * this.frequency);
        },

        onTimerEvent: function() {
          this.updater = new Ajax.Updater(this.container, this.url, this.options);
        }
      });
      function $(element) {
        if (arguments.length > 1) {
          for (var i = 0, elements = [], length = arguments.length; i < length; i++)
          elements.push($(arguments[i]));
          return elements;
        }
        if (Object.isString(element))
        element = document.getElementById(element);
        return Element.extend(element);
      }

      if (Prototype.BrowserFeatures.XPath) {
        document._getElementsByXPath = function(expression, parentElement) {
          var results = [];
          var query = document.evaluate(expression, $(parentElement) || document,
          null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
          for (var i = 0, length = query.snapshotLength; i < length; i++)
          results.push(Element.extend(query.snapshotItem(i)));
          return results;
        };
      }

      /*--------------------------------------------------------------------------*/

      if (!window.Node) var Node = { };

      if (!Node.ELEMENT_NODE) {
  // DOM level 2 ECMAScript Language Binding
        Object.extend(Node, {
          ELEMENT_NODE: 1,
          ATTRIBUTE_NODE: 2,
          TEXT_NODE: 3,
          CDATA_SECTION_NODE: 4,
          ENTITY_REFERENCE_NODE: 5,
          ENTITY_NODE: 6,
          PROCESSING_INSTRUCTION_NODE: 7,
          COMMENT_NODE: 8,
          DOCUMENT_NODE: 9,
          DOCUMENT_TYPE_NODE: 10,
          DOCUMENT_FRAGMENT_NODE: 11,
          NOTATION_NODE: 12
        });
      }

      (function() {
        var element = this.Element;
        this.Element = function(tagName, attributes) {
          attributes = attributes || { };
          tagName = tagName.toLowerCase();
          var cache = Element.cache;
          if (Prototype.Browser.IE && attributes.name) {
            tagName = '<' + tagName + ' name="' + attributes.name + '">';
            delete attributes.name;
            return Element.writeAttribute(document.createElement(tagName), attributes);
          }
          if (!cache[tagName]) cache[tagName] = Element.extend(document.createElement(tagName));
          return Element.writeAttribute(cache[tagName].cloneNode(false), attributes);
        };
        Object.extend(this.Element, element || { });
        if (element) this.Element.prototype = element.prototype;
      }).call(window);

      Element.cache = { };

      Element.Methods = {
        visible: function(element) {
          return $(element).style.display != 'none';
        },

        toggle: function(element) {
          element = $(element);
          Element[Element.visible(element) ? 'hide' : 'show'](element);
          return element;
        },

        hide: function(element) {
          element = $(element);
          element.style.display = 'none';
          return element;
        },

        show: function(element) {
          element = $(element);
          element.style.display = '';
          return element;
        },

        remove: function(element) {
          element = $(element);
          element.parentNode.removeChild(element);
          return element;
        },

        update: function(element, content) {
          element = $(element);
          if (content && content.toElement) content = content.toElement();
          if (Object.isElement(content)) return element.update().insert(content);
          content = Object.toHTML(content);
          element.innerHTML = content.stripScripts();
          content.evalScripts.bind(content).defer();
          return element;
        },

        replace: function(element, content) {
          element = $(element);
          if (content && content.toElement) content = content.toElement();
          else if (!Object.isElement(content)) {
            content = Object.toHTML(content);
            var range = element.ownerDocument.createRange();
            range.selectNode(element);
            content.evalScripts.bind(content).defer();
            content = range.createContextualFragment(content.stripScripts());
          }
          element.parentNode.replaceChild(content, element);
          return element;
        },

        insert: function(element, insertions) {
          element = $(element);

          if (Object.isString(insertions) || Object.isNumber(insertions) ||
          Object.isElement(insertions) || (insertions && (insertions.toElement || insertions.toHTML)))
          insertions = {bottom:insertions};

          var content, insert, tagName, childNodes;

          for (var position in insertions) {
            content  = insertions[position];
            position = position.toLowerCase();
            insert = Element._insertionTranslations[position];

            if (content && content.toElement) content = content.toElement();
            if (Object.isElement(content)) {
              insert(element, content);
              continue;
            }

            content = Object.toHTML(content);

            tagName = ((position == 'before' || position == 'after')
                ? element.parentNode : element).tagName.toUpperCase();

            childNodes = Element._getContentFromAnonymousElement(tagName, content.stripScripts());

            if (position == 'top' || position == 'after') childNodes.reverse();
            childNodes.each(insert.curry(element));

            content.evalScripts.bind(content).defer();
          }

          return element;
        },

        wrap: function(element, wrapper, attributes) {
          element = $(element);
          if (Object.isElement(wrapper))
          $(wrapper).writeAttribute(attributes || { });
          else if (Object.isString(wrapper)) wrapper = new Element(wrapper, attributes);
          else wrapper = new Element('div', wrapper);
          if (element.parentNode)
          element.parentNode.replaceChild(wrapper, element);
          wrapper.appendChild(element);
          return wrapper;
        },

        inspect: function(element) {
          element = $(element);
          var result = '<' + element.tagName.toLowerCase();
          $H({'id': 'id', 'className': 'class'}).each(function(pair) {
            var property = pair.first(), attribute = pair.last();
            var value = (element[property] || '').toString();
            if (value) result += ' ' + attribute + '=' + value.inspect(true);
          });
          return result + '>';
        },

        recursivelyCollect: function(element, property) {
          element = $(element);
          var elements = [];
          while (element = element[property])
          if (element.nodeType == 1)
          elements.push(Element.extend(element));
          return elements;
        },

        ancestors: function(element) {
          return $(element).recursivelyCollect('parentNode');
        },

        descendants: function(element) {
          return $(element).select("*");
        },

        firstDescendant: function(element) {
          element = $(element).firstChild;
          while (element && element.nodeType != 1) element = element.nextSibling;
          return $(element);
        },

        immediateDescendants: function(element) {
          if (!(element = $(element).firstChild)) return [];
          while (element && element.nodeType != 1) element = element.nextSibling;
          if (element) return [element].concat($(element).nextSiblings());
          return [];
        },

        previousSiblings: function(element) {
          return $(element).recursivelyCollect('previousSibling');
        },

        nextSiblings: function(element) {
          return $(element).recursivelyCollect('nextSibling');
        },

        siblings: function(element) {
          element = $(element);
          return element.previousSiblings().reverse().concat(element.nextSiblings());
        },

        match: function(element, selector) {
          if (Object.isString(selector))
          selector = new Selector(selector);
          return selector.match($(element));
        },

        up: function(element, expression, index) {
          element = $(element);
          if (arguments.length == 1) return $(element.parentNode);
          var ancestors = element.ancestors();
    return Object.isNumber(expression) ? ancestors[expression] :
        Selector.findElement(ancestors, expression, index);
        },

        down: function(element, expression, index) {
          element = $(element);
          if (arguments.length == 1) return element.firstDescendant();
    return Object.isNumber(expression) ? element.descendants()[expression] :
        Element.select(element, expression)[index || 0];
        },

        previous: function(element, expression, index) {
          element = $(element);
          if (arguments.length == 1) return $(Selector.handlers.previousElementSibling(element));
          var previousSiblings = element.previousSiblings();
    return Object.isNumber(expression) ? previousSiblings[expression] :
        Selector.findElement(previousSiblings, expression, index);
        },

        next: function(element, expression, index) {
          element = $(element);
          if (arguments.length == 1) return $(Selector.handlers.nextElementSibling(element));
          var nextSiblings = element.nextSiblings();
    return Object.isNumber(expression) ? nextSiblings[expression] :
        Selector.findElement(nextSiblings, expression, index);
        },

        select: function() {
          var args = $A(arguments), element = $(args.shift());
          return Selector.findChildElements(element, args);
        },

        adjacent: function() {
          var args = $A(arguments), element = $(args.shift());
          return Selector.findChildElements(element.parentNode, args).without(element);
        },

        identify: function(element) {
          element = $(element);
          var id = element.readAttribute('id'), self = arguments.callee;
          if (id) return id;
          do { id = 'anonymous_element_' + self.counter++ } while ($(id));
          element.writeAttribute('id', id);
          return id;
        },

        readAttribute: function(element, name) {
          element = $(element);
          if (Prototype.Browser.IE) {
            var t = Element._attributeTranslations.read;
            if (t.values[name]) return t.values[name](element, name);
            if (t.names[name]) name = t.names[name];
            if (name.include(':')) {
        return (!element.attributes || !element.attributes[name]) ? null :
            element.attributes[name].value;
            }
          }
          return element.getAttribute(name);
        },

        writeAttribute: function(element, name, value) {
          element = $(element);
          var attributes = { }, t = Element._attributeTranslations.write;

          if (typeof name == 'object') attributes = name;
          else attributes[name] = Object.isUndefined(value) ? true : value;

          for (var attr in attributes) {
            name = t.names[attr] || attr;
            value = attributes[attr];
            if (t.values[attr]) name = t.values[attr](element, value);
            if (value === false || value === null)
            element.removeAttribute(name);
            else if (value === true)
            element.setAttribute(name, name);
            else element.setAttribute(name, value);
          }
          return element;
        },

        getHeight: function(element) {
          return $(element).getDimensions().height;
        },

        getWidth: function(element) {
          return $(element).getDimensions().width;
        },

        classNames: function(element) {
          return new Element.ClassNames(element);
        },

        hasClassName: function(element, className) {
          if (!(element = $(element))) return;
          var elementClassName = element.className;
          return (elementClassName.length > 0 && (elementClassName == className ||
              new RegExp("(^|\\s)" + className + "(\\s|$)").test(elementClassName)));
        },

        addClassName: function(element, className) {
          if (!(element = $(element))) return;
          if (!element.hasClassName(className))
          element.className += (element.className ? ' ' : '') + className;
          return element;
        },

        removeClassName: function(element, className) {
          if (!(element = $(element))) return;
          element.className = element.className.replace(
          new RegExp("(^|\\s+)" + className + "(\\s+|$)"), ' ').strip();
          return element;
        },

        toggleClassName: function(element, className) {
          if (!(element = $(element))) return;
          return element[element.hasClassName(className) ?
              'removeClassName' : 'addClassName'](className);
        },

  // removes whitespace-only text node children
        cleanWhitespace: function(element) {
          element = $(element);
          var node = element.firstChild;
          while (node) {
            var nextNode = node.nextSibling;
            if (node.nodeType == 3 && !/\S/.test(node.nodeValue))
            element.removeChild(node);
            node = nextNode;
          }
          return element;
        },

        empty: function(element) {
          return $(element).innerHTML.blank();
        },

        descendantOf: function(element, ancestor) {
          element = $(element), ancestor = $(ancestor);

          if (element.compareDocumentPosition)
          return (element.compareDocumentPosition(ancestor) & 8) === 8;

          if (ancestor.contains)
          return ancestor.contains(element) && ancestor !== element;

          while (element = element.parentNode)
          if (element == ancestor) return true;

          return false;
        },

        scrollTo: function(element) {
          element = $(element);
          var pos = element.cumulativeOffset();
          window.scrollTo(pos[0], pos[1]);
          return element;
        },

        getStyle: function(element, style) {
          element = $(element);
          style = style == 'float' ? 'cssFloat' : style.camelize();
          var value = element.style[style];
          if (!value || value == 'auto') {
            var css = document.defaultView.getComputedStyle(element, null);
            value = css ? css[style] : null;
          }
          if (style == 'opacity') return value ? parseFloat(value) : 1.0;
          return value == 'auto' ? null : value;
        },

        getOpacity: function(element) {
          return $(element).getStyle('opacity');
        },

        setStyle: function(element, styles) {
          element = $(element);
          var elementStyle = element.style, match;
          if (Object.isString(styles)) {
            element.style.cssText += ';' + styles;
            return styles.include('opacity') ?
                element.setOpacity(styles.match(/opacity:\s*(\d?\.?\d*)/)[1]) : element;
          }
          for (var property in styles)
          if (property == 'opacity') element.setOpacity(styles[property]);
          else
            elementStyle[(property == 'float' || property == 'cssFloat') ?
          (Object.isUndefined(elementStyle.styleFloat) ? 'cssFloat' : 'styleFloat') :
                property] = styles[property];

          return element;
        },

        setOpacity: function(element, value) {
          element = $(element);
    element.style.opacity = (value == 1 || value === '') ? '' :
        (value < 0.00001) ? 0 : value;
    return element;
        },

        getDimensions: function(element) {
          element = $(element);
          var display = element.getStyle('display');
          if (display != 'none' && display != null) // Safari bug
          return {width: element.offsetWidth, height: element.offsetHeight};

    // All *Width and *Height properties give 0 on elements with display none,
    // so enable the element temporarily
          var els = element.style;
          var originalVisibility = els.visibility;
          var originalPosition = els.position;
          var originalDisplay = els.display;
          els.visibility = 'hidden';
          els.position = 'absolute';
          els.display = 'block';
          var originalWidth = element.clientWidth;
          var originalHeight = element.clientHeight;
          els.display = originalDisplay;
          els.position = originalPosition;
          els.visibility = originalVisibility;
          return {width: originalWidth, height: originalHeight};
        },

        makePositioned: function(element) {
          element = $(element);
          var pos = Element.getStyle(element, 'position');
          if (pos == 'static' || !pos) {
            element._madePositioned = true;
            element.style.position = 'relative';
      // Opera returns the offset relative to the positioning context, when an
      // element is position relative but top and left have not been defined
            if (Prototype.Browser.Opera) {
              element.style.top = 0;
              element.style.left = 0;
            }
          }
          return element;
        },

        undoPositioned: function(element) {
          element = $(element);
          if (element._madePositioned) {
            element._madePositioned = undefined;
            element.style.position =
                element.style.top =
                element.style.left =
                element.style.bottom =
                element.style.right = '';
          }
          return element;
        },

        makeClipping: function(element) {
          element = $(element);
          if (element._overflow) return element;
          element._overflow = Element.getStyle(element, 'overflow') || 'auto';
          if (element._overflow !== 'hidden')
          element.style.overflow = 'hidden';
          return element;
        },

        undoClipping: function(element) {
          element = $(element);
          if (!element._overflow) return element;
          element.style.overflow = element._overflow == 'auto' ? '' : element._overflow;
          element._overflow = null;
          return element;
        },

        cumulativeOffset: function(element) {
          var valueT = 0, valueL = 0;
          do {
            valueT += element.offsetTop  || 0;
            valueL += element.offsetLeft || 0;
            element = element.offsetParent;
          } while (element);
          return Element._returnOffset(valueL, valueT);
        },

        positionedOffset: function(element) {
          var valueT = 0, valueL = 0;
          do {
            valueT += element.offsetTop  || 0;
            valueL += element.offsetLeft || 0;
            element = element.offsetParent;
            if (element) {
              if (element.tagName.toUpperCase() == 'BODY') break;
              var p = Element.getStyle(element, 'position');
              if (p !== 'static') break;
            }
          } while (element);
          return Element._returnOffset(valueL, valueT);
        },

        absolutize: function(element) {
          element = $(element);
          if (element.getStyle('position') == 'absolute') return element;
    // Position.prepare(); // To be done manually by Scripty when it needs it.

          var offsets = element.positionedOffset();
          var top     = offsets[1];
          var left    = offsets[0];
          var width   = element.clientWidth;
          var height  = element.clientHeight;

          element._originalLeft   = left - parseFloat(element.style.left  || 0);
          element._originalTop    = top  - parseFloat(element.style.top || 0);
          element._originalWidth  = element.style.width;
          element._originalHeight = element.style.height;

          element.style.position = 'absolute';
          element.style.top    = top + 'px';
          element.style.left   = left + 'px';
          element.style.width  = width + 'px';
          element.style.height = height + 'px';
          return element;
        },

        relativize: function(element) {
          element = $(element);
          if (element.getStyle('position') == 'relative') return element;
    // Position.prepare(); // To be done manually by Scripty when it needs it.

          element.style.position = 'relative';
          var top  = parseFloat(element.style.top  || 0) - (element._originalTop || 0);
          var left = parseFloat(element.style.left || 0) - (element._originalLeft || 0);

          element.style.top    = top + 'px';
          element.style.left   = left + 'px';
          element.style.height = element._originalHeight;
          element.style.width  = element._originalWidth;
          return element;
        },

        cumulativeScrollOffset: function(element) {
          var valueT = 0, valueL = 0;
          do {
            valueT += element.scrollTop  || 0;
            valueL += element.scrollLeft || 0;
            element = element.parentNode;
          } while (element);
          return Element._returnOffset(valueL, valueT);
        },

        getOffsetParent: function(element) {
          if (element.offsetParent) return $(element.offsetParent);
          if (element == document.body) return $(element);

          while ((element = element.parentNode) && element != document.body)
          if (Element.getStyle(element, 'position') != 'static')
          return $(element);

          return $(document.body);
        },

        viewportOffset: function(forElement) {
          var valueT = 0, valueL = 0;

          var element = forElement;
          do {
            valueT += element.offsetTop  || 0;
            valueL += element.offsetLeft || 0;

      // Safari fix
            if (element.offsetParent == document.body &&
            Element.getStyle(element, 'position') == 'absolute') break;

          } while (element = element.offsetParent);

          element = forElement;
          do {
            if (!Prototype.Browser.Opera || (element.tagName && (element.tagName.toUpperCase() == 'BODY'))) {
              valueT -= element.scrollTop  || 0;
              valueL -= element.scrollLeft || 0;
            }
          } while (element = element.parentNode);

          return Element._returnOffset(valueL, valueT);
        },

        clonePosition: function(element, source) {
          var options = Object.extend({
            setLeft:    true,
            setTop:     true,
            setWidth:   true,
            setHeight:  true,
            offsetTop:  0,
            offsetLeft: 0
          }, arguments[2] || { });

    // find page position of source
          source = $(source);
          var p = source.viewportOffset();

    // find coordinate system to use
          element = $(element);
          var delta = [0, 0];
          var parent = null;
    // delta [0,0] will do fine with position: fixed elements,
    // position:absolute needs offsetParent deltas
          if (Element.getStyle(element, 'position') == 'absolute') {
            parent = element.getOffsetParent();
            delta = parent.viewportOffset();
          }

    // correct by body offsets (fixes Safari)
          if (parent == document.body) {
            delta[0] -= document.body.offsetLeft;
            delta[1] -= document.body.offsetTop;
          }

    // set position
          if (options.setLeft)   element.style.left  = (p[0] - delta[0] + options.offsetLeft) + 'px';
          if (options.setTop)    element.style.top   = (p[1] - delta[1] + options.offsetTop) + 'px';
          if (options.setWidth)  element.style.width = source.offsetWidth + 'px';
          if (options.setHeight) element.style.height = source.offsetHeight + 'px';
          return element;
        }
      };

      Element.Methods.identify.counter = 1;

      Object.extend(Element.Methods, {
        getElementsBySelector: Element.Methods.select,
        childElements: Element.Methods.immediateDescendants
      });

      Element._attributeTranslations = {
        write: {
          names: {
            className: 'class',
            htmlFor:   'for'
          },
          values: { }
        }
      };

      if (Prototype.Browser.Opera) {
        Element.Methods.getStyle = Element.Methods.getStyle.wrap(
        function(proceed, element, style) {
          switch (style) {
            case 'left': case 'top': case 'right': case 'bottom':
                if (proceed(element, 'position') === 'static') return null;
            case 'height': case 'width':
          // returns '0px' for hidden elements; we want it to return null
                if (!Element.visible(element)) return null;

          // returns the border-box dimensions rather than the content-box
          // dimensions, so we subtract padding and borders from the value
            var dim = parseInt(proceed(element, style), 10);

            if (dim !== element['offset' + style.capitalize()])
            return dim + 'px';

            var properties;
            if (style === 'height') {
              properties = ['border-top-width', 'padding-top',
              'padding-bottom', 'border-bottom-width'];
            }
            else {
              properties = ['border-left-width', 'padding-left',
              'padding-right', 'border-right-width'];
            }
            return properties.inject(dim, function(memo, property) {
              var val = proceed(element, property);
              return val === null ? memo : memo - parseInt(val, 10);
            }) + 'px';
            default: return proceed(element, style);
          }
        }
  );

  Element.Methods.readAttribute = Element.Methods.readAttribute.wrap(
  function(proceed, element, attribute) {
    if (attribute === 'title') return element.title;
    return proceed(element, attribute);
  }
  );
      }

      else if (Prototype.Browser.IE) {
  // IE doesn't report offsets correctly for static elements, so we change them
  // to "relative" to get the values, then change them back.
        Element.Methods.getOffsetParent = Element.Methods.getOffsetParent.wrap(
        function(proceed, element) {
          element = $(element);
      // IE throws an error if element is not in document
          try { element.offsetParent }
          catch(e) { return $(document.body) }
          var position = element.getStyle('position');
          if (position !== 'static') return proceed(element);
          element.setStyle({ position: 'relative' });
          var value = proceed(element);
          element.setStyle({ position: position });
          return value;
        }
  );

  $w('positionedOffset viewportOffset').each(function(method) {
    Element.Methods[method] = Element.Methods[method].wrap(
    function(proceed, element) {
      element = $(element);
      try { element.offsetParent }
      catch(e) { return Element._returnOffset(0,0) }
      var position = element.getStyle('position');
      if (position !== 'static') return proceed(element);
        // Trigger hasLayout on the offset parent so that IE6 reports
        // accurate offsetTop and offsetLeft values for position: fixed.
      var offsetParent = element.getOffsetParent();
      if (offsetParent && offsetParent.getStyle('position') === 'fixed')
      offsetParent.setStyle({ zoom: 1 });
      element.setStyle({ position: 'relative' });
      var value = proceed(element);
      element.setStyle({ position: position });
      return value;
    }
    );
  });

  Element.Methods.cumulativeOffset = Element.Methods.cumulativeOffset.wrap(
  function(proceed, element) {
    try { element.offsetParent }
    catch(e) { return Element._returnOffset(0,0) }
    return proceed(element);
  }
  );

  Element.Methods.getStyle = function(element, style) {
    element = $(element);
    style = (style == 'float' || style == 'cssFloat') ? 'styleFloat' : style.camelize();
    var value = element.style[style];
    if (!value && element.currentStyle) value = element.currentStyle[style];

    if (style == 'opacity') {
      if (value = (element.getStyle('filter') || '').match(/alpha\(opacity=(.*)\)/))
      if (value[1]) return parseFloat(value[1]) / 100;
      return 1.0;
    }

    if (value == 'auto') {
      if ((style == 'width' || style == 'height') && (element.getStyle('display') != 'none'))
      return element['offset' + style.capitalize()] + 'px';
      return null;
    }
    return value;
  };

  Element.Methods.setOpacity = function(element, value) {
    function stripAlpha(filter){
      return filter.replace(/alpha\([^\)]*\)/gi,'');
    }
    element = $(element);
    var currentStyle = element.currentStyle;
    if ((currentStyle && !currentStyle.hasLayout) ||
    (!currentStyle && element.style.zoom == 'normal'))
    element.style.zoom = 1;

    var filter = element.getStyle('filter'), style = element.style;
    if (value == 1 || value === '') {
      (filter = stripAlpha(filter)) ?
          style.filter = filter : style.removeAttribute('filter');
      return element;
    } else if (value < 0.00001) value = 0;
    style.filter = stripAlpha(filter) +
        'alpha(opacity=' + (value * 100) + ')';
    return element;
  };

  Element._attributeTranslations = {
    read: {
      names: {
        'class': 'className',
        'for':   'htmlFor'
      },
      values: {
        _getAttr: function(element, attribute) {
          return element.getAttribute(attribute, 2);
        },
        _getAttrNode: function(element, attribute) {
          var node = element.getAttributeNode(attribute);
          return node ? node.value : "";
        },
        _getEv: function(element, attribute) {
          attribute = element.getAttribute(attribute);
          return attribute ? attribute.toString().slice(23, -2) : null;
        },
        _flag: function(element, attribute) {
          return $(element).hasAttribute(attribute) ? attribute : null;
        },
        style: function(element) {
          return element.style.cssText.toLowerCase();
        },
        title: function(element) {
          return element.title;
        }
      }
    }
  };

  Element._attributeTranslations.write = {
    names: Object.extend({
      cellpadding: 'cellPadding',
      cellspacing: 'cellSpacing'
    }, Element._attributeTranslations.read.names),
    values: {
      checked: function(element, value) {
        element.checked = !!value;
      },

      style: function(element, value) {
        element.style.cssText = value ? value : '';
      }
    }
  };

  Element._attributeTranslations.has = {};

  $w('colSpan rowSpan vAlign dateTime accessKey tabIndex ' +
      'encType maxLength readOnly longDesc frameBorder').each(function(attr) {
    Element._attributeTranslations.write.names[attr.toLowerCase()] = attr;
    Element._attributeTranslations.has[attr.toLowerCase()] = attr;
      });

      (function(v) {
        Object.extend(v, {
          href:        v._getAttr,
          src:         v._getAttr,
          type:        v._getAttr,
          action:      v._getAttrNode,
          disabled:    v._flag,
          checked:     v._flag,
          readonly:    v._flag,
          multiple:    v._flag,
          onload:      v._getEv,
          onunload:    v._getEv,
          onclick:     v._getEv,
          ondblclick:  v._getEv,
          onmousedown: v._getEv,
          onmouseup:   v._getEv,
          onmouseover: v._getEv,
          onmousemove: v._getEv,
          onmouseout:  v._getEv,
          onfocus:     v._getEv,
          onblur:      v._getEv,
          onkeypress:  v._getEv,
          onkeydown:   v._getEv,
          onkeyup:     v._getEv,
          onsubmit:    v._getEv,
          onreset:     v._getEv,
          onselect:    v._getEv,
          onchange:    v._getEv
        });
      })(Element._attributeTranslations.read.values);
      }

      else if (Prototype.Browser.Gecko && /rv:1\.8\.0/.test(navigator.userAgent)) {
        Element.Methods.setOpacity = function(element, value) {
          element = $(element);
    element.style.opacity = (value == 1) ? 0.999999 :
        (value === '') ? '' : (value < 0.00001) ? 0 : value;
    return element;
        };
      }

      else if (Prototype.Browser.WebKit) {
        Element.Methods.setOpacity = function(element, value) {
          element = $(element);
    element.style.opacity = (value == 1 || value === '') ? '' :
        (value < 0.00001) ? 0 : value;

    if (value == 1)
    if(element.tagName.toUpperCase() == 'IMG' && element.width) {
      element.width++; element.width--;
    } else try {
      var n = document.createTextNode(' ');
      element.appendChild(n);
      element.removeChild(n);
    } catch (e) { }

    return element;
        };

  // Safari returns margins on body which is incorrect if the child is absolutely
  // positioned.  For performance reasons, redefine Element#cumulativeOffset for
  // KHTML/WebKit only.
        Element.Methods.cumulativeOffset = function(element) {
          var valueT = 0, valueL = 0;
          do {
            valueT += element.offsetTop  || 0;
            valueL += element.offsetLeft || 0;
            if (element.offsetParent == document.body)
            if (Element.getStyle(element, 'position') == 'absolute') break;

            element = element.offsetParent;
          } while (element);

          return Element._returnOffset(valueL, valueT);
        };
      }

      if (Prototype.Browser.IE || Prototype.Browser.Opera) {
  // IE and Opera are missing .innerHTML support for TABLE-related and SELECT elements
        Element.Methods.update = function(element, content) {
          element = $(element);

          if (content && content.toElement) content = content.toElement();
          if (Object.isElement(content)) return element.update().insert(content);

          content = Object.toHTML(content);
          var tagName = element.tagName.toUpperCase();

          if (tagName in Element._insertionTranslations.tags) {
            $A(element.childNodes).each(function(node) { element.removeChild(node) });
            Element._getContentFromAnonymousElement(tagName, content.stripScripts())
                .each(function(node) { element.appendChild(node) });
          }
          else element.innerHTML = content.stripScripts();

          content.evalScripts.bind(content).defer();
          return element;
        };
      }

      if ('outerHTML' in document.createElement('div')) {
        Element.Methods.replace = function(element, content) {
          element = $(element);

          if (content && content.toElement) content = content.toElement();
          if (Object.isElement(content)) {
            element.parentNode.replaceChild(content, element);
            return element;
          }

          content = Object.toHTML(content);
          var parent = element.parentNode, tagName = parent.tagName.toUpperCase();

          if (Element._insertionTranslations.tags[tagName]) {
            var nextSibling = element.next();
            var fragments = Element._getContentFromAnonymousElement(tagName, content.stripScripts());
            parent.removeChild(element);
            if (nextSibling)
            fragments.each(function(node) { parent.insertBefore(node, nextSibling) });
            else
              fragments.each(function(node) { parent.appendChild(node) });
          }
          else element.outerHTML = content.stripScripts();

          content.evalScripts.bind(content).defer();
          return element;
        };
      }

      Element._returnOffset = function(l, t) {
        var result = [l, t];
        result.left = l;
        result.top = t;
        return result;
      };

      Element._getContentFromAnonymousElement = function(tagName, html) {
        var div = new Element('div'), t = Element._insertionTranslations.tags[tagName];
        if (t) {
          div.innerHTML = t[0] + html + t[1];
          t[2].times(function() { div = div.firstChild });
        } else div.innerHTML = html;
        return $A(div.childNodes);
      };

      Element._insertionTranslations = {
        before: function(element, node) {
          element.parentNode.insertBefore(node, element);
        },
        top: function(element, node) {
          element.insertBefore(node, element.firstChild);
        },
        bottom: function(element, node) {
          element.appendChild(node);
        },
        after: function(element, node) {
          element.parentNode.insertBefore(node, element.nextSibling);
        },
        tags: {
          TABLE:  ['<table>',                '</table>',                   1],
          TBODY:  ['<table><tbody>',         '</tbody></table>',           2],
          TR:     ['<table><tbody><tr>',     '</tr></tbody></table>',      3],
          TD:     ['<table><tbody><tr><td>', '</td></tr></tbody></table>', 4],
          SELECT: ['<select>',               '</select>',                  1]
        }
      };

      (function() {
        Object.extend(this.tags, {
          THEAD: this.tags.TBODY,
          TFOOT: this.tags.TBODY,
          TH:    this.tags.TD
        });
      }).call(Element._insertionTranslations);

      Element.Methods.Simulated = {
        hasAttribute: function(element, attribute) {
          attribute = Element._attributeTranslations.has[attribute] || attribute;
          var node = $(element).getAttributeNode(attribute);
          return !!(node && node.specified);
        }
      };

      Element.Methods.ByTag = { };

      Object.extend(Element, Element.Methods);

      if (!Prototype.BrowserFeatures.ElementExtensions &&
      document.createElement('div')['__proto__']) {
        window.HTMLElement = { };
        window.HTMLElement.prototype = document.createElement('div')['__proto__'];
        Prototype.BrowserFeatures.ElementExtensions = true;
      }

      Element.extend = (function() {
        if (Prototype.BrowserFeatures.SpecificElementExtensions)
        return Prototype.K;

        var Methods = { }, ByTag = Element.Methods.ByTag;

        var extend = Object.extend(function(element) {
          if (!element || element._extendedByPrototype ||
          element.nodeType != 1 || element == window) return element;

          var methods = Object.clone(Methods),
          tagName = element.tagName.toUpperCase(), property, value;

    // extend methods for specific tags
          if (ByTag[tagName]) Object.extend(methods, ByTag[tagName]);

          for (property in methods) {
            value = methods[property];
            if (Object.isFunction(value) && !(property in element))
            element[property] = value.methodize();
          }

          element._extendedByPrototype = Prototype.emptyFunction;
          return element;

        }, {
          refresh: function() {
      // extend methods for all tags (Safari doesn't need this)
            if (!Prototype.BrowserFeatures.ElementExtensions) {
              Object.extend(Methods, Element.Methods);
              Object.extend(Methods, Element.Methods.Simulated);
            }
          }
        });

        extend.refresh();
        return extend;
      })();

      Element.hasAttribute = function(element, attribute) {
        if (element.hasAttribute) return element.hasAttribute(attribute);
        return Element.Methods.Simulated.hasAttribute(element, attribute);
      };

      Element.addMethods = function(methods) {
        var F = Prototype.BrowserFeatures, T = Element.Methods.ByTag;

        if (!methods) {
          Object.extend(Form, Form.Methods);
          Object.extend(Form.Element, Form.Element.Methods);
          Object.extend(Element.Methods.ByTag, {
            "FORM":     Object.clone(Form.Methods),
            "INPUT":    Object.clone(Form.Element.Methods),
            "SELECT":   Object.clone(Form.Element.Methods),
            "TEXTAREA": Object.clone(Form.Element.Methods)
          });
        }

        if (arguments.length == 2) {
          var tagName = methods;
          methods = arguments[1];
        }

        if (!tagName) Object.extend(Element.Methods, methods || { });
        else {
          if (Object.isArray(tagName)) tagName.each(extend);
          else extend(tagName);
        }

        function extend(tagName) {
          tagName = tagName.toUpperCase();
          if (!Element.Methods.ByTag[tagName])
          Element.Methods.ByTag[tagName] = { };
          Object.extend(Element.Methods.ByTag[tagName], methods);
        }

        function copy(methods, destination, onlyIfAbsent) {
          onlyIfAbsent = onlyIfAbsent || false;
          for (var property in methods) {
            var value = methods[property];
            if (!Object.isFunction(value)) continue;
            if (!onlyIfAbsent || !(property in destination))
            destination[property] = value.methodize();
          }
        }

        function findDOMClass(tagName) {
          var klass;
          var trans = {
            "OPTGROUP": "OptGroup", "TEXTAREA": "TextArea", "P": "Paragraph",
            "FIELDSET": "FieldSet", "UL": "UList", "OL": "OList", "DL": "DList",
            "DIR": "Directory", "H1": "Heading", "H2": "Heading", "H3": "Heading",
            "H4": "Heading", "H5": "Heading", "H6": "Heading", "Q": "Quote",
      "INS": "Mod", "DEL": "Mod", "A": "Anchor", "IMG": "Image", "CAPTION":
      "TableCaption", "COL": "TableCol", "COLGROUP": "TableCol", "THEAD":
      "TableSection", "TFOOT": "TableSection", "TBODY": "TableSection", "TR":
      "TableRow", "TH": "TableCell", "TD": "TableCell", "FRAMESET":
          "FrameSet", "IFRAME": "IFrame"
          };
          if (trans[tagName]) klass = 'HTML' + trans[tagName] + 'Element';
          if (window[klass]) return window[klass];
          klass = 'HTML' + tagName + 'Element';
          if (window[klass]) return window[klass];
          klass = 'HTML' + tagName.capitalize() + 'Element';
          if (window[klass]) return window[klass];

          window[klass] = { };
          window[klass].prototype = document.createElement(tagName)['__proto__'];
          return window[klass];
        }

        if (F.ElementExtensions) {
          copy(Element.Methods, HTMLElement.prototype);
          copy(Element.Methods.Simulated, HTMLElement.prototype, true);
        }

        if (F.SpecificElementExtensions) {
          for (var tag in Element.Methods.ByTag) {
            var klass = findDOMClass(tag);
            if (Object.isUndefined(klass)) continue;
            copy(T[tag], klass.prototype);
          }
        }

        Object.extend(Element, Element.Methods);
        delete Element.ByTag;

        if (Element.extend.refresh) Element.extend.refresh();
        Element.cache = { };
      };

      document.viewport = {
        getDimensions: function() {
          var dimensions = { }, B = Prototype.Browser;
          $w('width height').each(function(d) {
            var D = d.capitalize();
            if (B.WebKit && !document.evaluate) {
        // Safari <3.0 needs self.innerWidth/Height
              dimensions[d] = self['inner' + D];
            } else if (B.Opera && parseFloat(window.opera.version()) < 9.5) {
        // Opera <9.5 needs document.body.clientWidth/Height
              dimensions[d] = document.body['client' + D]
            } else {
                dimensions[d] = document.documentElement['client' + D];
            }
          });
          return dimensions;
        },

        getWidth: function() {
          return this.getDimensions().width;
        },

        getHeight: function() {
          return this.getDimensions().height;
        },

        getScrollOffsets: function() {
          return Element._returnOffset(
          window.pageXOffset || document.documentElement.scrollLeft || document.body.scrollLeft,
          window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop);
        }
      };
/* Portions of the Selector class are derived from Jack Slocum's DomQuery,
      * part of YUI-Ext version 0.40, distributed under the terms of an MIT-style
 * license.  Please see http://www.yui-ext.com/ for more information. */

      var Selector = Class.create({
        initialize: function(expression) {
          this.expression = expression.strip();

          if (this.shouldUseSelectorsAPI()) {
            this.mode = 'selectorsAPI';
          } else if (this.shouldUseXPath()) {
            this.mode = 'xpath';
            this.compileXPathMatcher();
          } else {
            this.mode = "normal";
            this.compileMatcher();
          }

        },

        shouldUseXPath: function() {
          if (!Prototype.BrowserFeatures.XPath) return false;

          var e = this.expression;

    // Safari 3 chokes on :*-of-type and :empty
          if (Prototype.Browser.WebKit &&
          (e.include("-of-type") || e.include(":empty")))
          return false;

    // XPath can't do namespaced attributes, nor can it read
    // the "checked" property from DOM nodes
          if ((/(\[[\w-]*?:|:checked)/).test(e))
          return false;

          return true;
        },

        shouldUseSelectorsAPI: function() {
          if (!Prototype.BrowserFeatures.SelectorsAPI) return false;

          if (!Selector._div) Selector._div = new Element('div');

    // Make sure the browser treats the selector as valid. Test on an
    // isolated element to minimize cost of this check.
          try {
            Selector._div.querySelector(this.expression);
          } catch(e) {
            return false;
          }

          return true;
        },

        compileMatcher: function() {
          var e = this.expression, ps = Selector.patterns, h = Selector.handlers,
          c = Selector.criteria, le, p, m;

          if (Selector._cache[e]) {
            this.matcher = Selector._cache[e];
            return;
          }

          this.matcher = ["this.matcher = function(root) {",
          "var r = root, h = Selector.handlers, c = false, n;"];

          while (e && le != e && (/\S/).test(e)) {
            le = e;
            for (var i in ps) {
              p = ps[i];
              if (m = e.match(p)) {
          this.matcher.push(Object.isFunction(c[i]) ? c[i](m) :
              new Template(c[i]).evaluate(m));
          e = e.replace(m[0], '');
          break;
              }
            }
          }

          this.matcher.push("return h.unique(n);\n}");
          eval(this.matcher.join('\n'));
          Selector._cache[this.expression] = this.matcher;
        },

        compileXPathMatcher: function() {
          var e = this.expression, ps = Selector.patterns,
          x = Selector.xpath, le, m;

          if (Selector._cache[e]) {
            this.xpath = Selector._cache[e]; return;
          }

          this.matcher = ['.//*'];
          while (e && le != e && (/\S/).test(e)) {
            le = e;
            for (var i in ps) {
              if (m = e.match(ps[i])) {
          this.matcher.push(Object.isFunction(x[i]) ? x[i](m) :
              new Template(x[i]).evaluate(m));
          e = e.replace(m[0], '');
          break;
              }
            }
          }

          this.xpath = this.matcher.join('');
          Selector._cache[this.expression] = this.xpath;
        },

        findElements: function(root) {
          root = root || document;
          var e = this.expression, results;

          switch (this.mode) {
            case 'selectorsAPI':
        // querySelectorAll queries document-wide, then filters to descendants
        // of the context element. That's not what we want.
        // Add an explicit context to the selector if necessary.
                if (root !== document) {
              var oldId = root.id, id = $(root).identify();
              e = "#" + id + " " + e;
                }

                results = $A(root.querySelectorAll(e)).map(Element.extend);
                root.id = oldId;

                return results;
            case 'xpath':
                return document._getElementsByXPath(this.xpath, root);
            default:
                return this.matcher(root);
          }
        },

        match: function(element) {
          this.tokens = [];

          var e = this.expression, ps = Selector.patterns, as = Selector.assertions;
          var le, p, m;

          while (e && le !== e && (/\S/).test(e)) {
            le = e;
            for (var i in ps) {
              p = ps[i];
              if (m = e.match(p)) {
          // use the Selector.assertions methods unless the selector
          // is too complex.
                if (as[i]) {
                  this.tokens.push([i, Object.clone(m)]);
                  e = e.replace(m[0], '');
                } else {
            // reluctantly do a document-wide search
            // and look for a match in the array
                  return this.findElements(document).include(element);
                }
              }
            }
          }

          var match = true, name, matches;
          for (var i = 0, token; token = this.tokens[i]; i++) {
            name = token[0], matches = token[1];
            if (!Selector.assertions[name](element, matches)) {
              match = false; break;
            }
          }

          return match;
        },

        toString: function() {
          return this.expression;
        },

        inspect: function() {
          return "#<Selector:" + this.expression.inspect() + ">";
        }
      });

      Object.extend(Selector, {
        _cache: { },

        xpath: {
          descendant:   "//*",
          child:        "/*",
          adjacent:     "/following-sibling::*[1]",
          laterSibling: '/following-sibling::*',
          tagName:      function(m) {
            if (m[1] == '*') return '';
            return "[local-name()='" + m[1].toLowerCase() +
                "' or local-name()='" + m[1].toUpperCase() + "']";
          },
          className:    "[contains(concat(' ', @class, ' '), ' #{1} ')]",
          id:           "[@id='#{1}']",
          attrPresence: function(m) {
            m[1] = m[1].toLowerCase();
            return new Template("[@#{1}]").evaluate(m);
          },
          attr: function(m) {
            m[1] = m[1].toLowerCase();
            m[3] = m[5] || m[6];
            return new Template(Selector.xpath.operators[m[2]]).evaluate(m);
          },
          pseudo: function(m) {
            var h = Selector.xpath.pseudos[m[1]];
            if (!h) return '';
            if (Object.isFunction(h)) return h(m);
            return new Template(Selector.xpath.pseudos[m[1]]).evaluate(m);
          },
          operators: {
            '=':  "[@#{1}='#{3}']",
            '!=': "[@#{1}!='#{3}']",
            '^=': "[starts-with(@#{1}, '#{3}')]",
            '$=': "[substring(@#{1}, (string-length(@#{1}) - string-length('#{3}') + 1))='#{3}']",
            '*=': "[contains(@#{1}, '#{3}')]",
            '~=': "[contains(concat(' ', @#{1}, ' '), ' #{3} ')]",
            '|=': "[contains(concat('-', @#{1}, '-'), '-#{3}-')]"
          },
          pseudos: {
            'first-child': '[not(preceding-sibling::*)]',
            'last-child':  '[not(following-sibling::*)]',
            'only-child':  '[not(preceding-sibling::* or following-sibling::*)]',
            'empty':       "[count(*) = 0 and (count(text()) = 0)]",
            'checked':     "[@checked]",
            'disabled':    "[(@disabled) and (@type!='hidden')]",
            'enabled':     "[not(@disabled) and (@type!='hidden')]",
            'not': function(m) {
              var e = m[6], p = Selector.patterns,
              x = Selector.xpath, le, v;

              var exclusion = [];
              while (e && le != e && (/\S/).test(e)) {
                le = e;
                for (var i in p) {
                  if (m = e.match(p[i])) {
                    v = Object.isFunction(x[i]) ? x[i](m) : new Template(x[i]).evaluate(m);
                    exclusion.push("(" + v.substring(1, v.length - 1) + ")");
                    e = e.replace(m[0], '');
                    break;
                  }
                }
              }
              return "[not(" + exclusion.join(" and ") + ")]";
            },
            'nth-child':      function(m) {
              return Selector.xpath.pseudos.nth("(count(./preceding-sibling::*) + 1) ", m);
            },
            'nth-last-child': function(m) {
              return Selector.xpath.pseudos.nth("(count(./following-sibling::*) + 1) ", m);
            },
            'nth-of-type':    function(m) {
              return Selector.xpath.pseudos.nth("position() ", m);
            },
            'nth-last-of-type': function(m) {
              return Selector.xpath.pseudos.nth("(last() + 1 - position()) ", m);
            },
            'first-of-type':  function(m) {
              m[6] = "1"; return Selector.xpath.pseudos['nth-of-type'](m);
            },
            'last-of-type':   function(m) {
              m[6] = "1"; return Selector.xpath.pseudos['nth-last-of-type'](m);
            },
            'only-of-type':   function(m) {
              var p = Selector.xpath.pseudos; return p['first-of-type'](m) + p['last-of-type'](m);
            },
            nth: function(fragment, m) {
              var mm, formula = m[6], predicate;
              if (formula == 'even') formula = '2n+0';
              if (formula == 'odd')  formula = '2n+1';
              if (mm = formula.match(/^(\d+)$/)) // digit only
              return '[' + fragment + "= " + mm[1] + ']';
              if (mm = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
                if (mm[1] == "-") mm[1] = -1;
                var a = mm[1] ? Number(mm[1]) : 1;
                var b = mm[2] ? Number(mm[2]) : 0;
                predicate = "[((#{fragment} - #{b}) mod #{a} = 0) and " +
                    "((#{fragment} - #{b}) div #{a} >= 0)]";
                return new Template(predicate).evaluate({
                  fragment: fragment, a: a, b: b });
              }
            }
          }
        },

        criteria: {
          tagName:      'n = h.tagName(n, r, "#{1}", c);      c = false;',
          className:    'n = h.className(n, r, "#{1}", c);    c = false;',
          id:           'n = h.id(n, r, "#{1}", c);           c = false;',
          attrPresence: 'n = h.attrPresence(n, r, "#{1}", c); c = false;',
          attr: function(m) {
            m[3] = (m[5] || m[6]);
            return new Template('n = h.attr(n, r, "#{1}", "#{3}", "#{2}", c); c = false;').evaluate(m);
          },
          pseudo: function(m) {
            if (m[6]) m[6] = m[6].replace(/"/g, '\\"');
            return new Template('n = h.pseudo(n, "#{1}", "#{6}", r, c); c = false;').evaluate(m);
          },
          descendant:   'c = "descendant";',
          child:        'c = "child";',
          adjacent:     'c = "adjacent";',
          laterSibling: 'c = "laterSibling";'
        },

        patterns: {
    // combinators must be listed first
    // (and descendant needs to be last combinator)
          laterSibling: /^\s*~\s*/,
          child:        /^\s*>\s*/,
          adjacent:     /^\s*\+\s*/,
          descendant:   /^\s/,

    // selectors follow
          tagName:      /^\s*(\*|[\w\-]+)(\b|$)?/,
          id:           /^#([\w\-\*]+)(\b|$)/,
          className:    /^\.([\w\-\*]+)(\b|$)/,
    pseudo:
/^:((first|last|nth|nth-last|only)(-child|-of-type)|empty|checked|(en|dis)abled|not)(\((.*?)\))?(\b|$|(?=\s|[:+~>]))/,
    attrPresence: /^\[((?:[\w]+:)?[\w]+)\]/,
    attr:         /\[((?:[\w-]*:)?[\w-]+)\s*(?:([!^$*~|]?=)\s*((['"])([^\4]*?)\4|([^'"][^\]]*?)))?\]/
        },

  // for Selector.match and Element#match
        assertions: {
          tagName: function(element, matches) {
            return matches[1].toUpperCase() == element.tagName.toUpperCase();
          },

          className: function(element, matches) {
            return Element.hasClassName(element, matches[1]);
          },

          id: function(element, matches) {
            return element.id === matches[1];
          },

          attrPresence: function(element, matches) {
            return Element.hasAttribute(element, matches[1]);
          },

          attr: function(element, matches) {
            var nodeValue = Element.readAttribute(element, matches[1]);
            return nodeValue && Selector.operators[matches[2]](nodeValue, matches[5] || matches[6]);
          }
        },

        handlers: {
    // UTILITY FUNCTIONS
    // joins two collections
          concat: function(a, b) {
            for (var i = 0, node; node = b[i]; i++)
            a.push(node);
            return a;
          },

    // marks an array of nodes for counting
          mark: function(nodes) {
            var _true = Prototype.emptyFunction;
            for (var i = 0, node; node = nodes[i]; i++)
            node._countedByPrototype = _true;
            return nodes;
          },

          unmark: function(nodes) {
            for (var i = 0, node; node = nodes[i]; i++)
            node._countedByPrototype = undefined;
            return nodes;
          },

    // mark each child node with its position (for nth calls)
    // "ofType" flag indicates whether we're indexing for nth-of-type
    // rather than nth-child
          index: function(parentNode, reverse, ofType) {
            parentNode._countedByPrototype = Prototype.emptyFunction;
            if (reverse) {
              for (var nodes = parentNode.childNodes, i = nodes.length - 1, j = 1; i >= 0; i--) {
                var node = nodes[i];
                if (node.nodeType == 1 && (!ofType || node._countedByPrototype)) node.nodeIndex = j++;
              }
            } else {
              for (var i = 0, j = 1, nodes = parentNode.childNodes; node = nodes[i]; i++)
              if (node.nodeType == 1 && (!ofType || node._countedByPrototype)) node.nodeIndex = j++;
            }
          },

    // filters out duplicates and extends all nodes
          unique: function(nodes) {
            if (nodes.length == 0) return nodes;
            var results = [], n;
            for (var i = 0, l = nodes.length; i < l; i++)
            if (!(n = nodes[i])._countedByPrototype) {
              n._countedByPrototype = Prototype.emptyFunction;
              results.push(Element.extend(n));
            }
            return Selector.handlers.unmark(results);
          },

    // COMBINATOR FUNCTIONS
          descendant: function(nodes) {
            var h = Selector.handlers;
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            h.concat(results, node.getElementsByTagName('*'));
            return results;
          },

          child: function(nodes) {
            var h = Selector.handlers;
            for (var i = 0, results = [], node; node = nodes[i]; i++) {
              for (var j = 0, child; child = node.childNodes[j]; j++)
              if (child.nodeType == 1 && child.tagName != '!') results.push(child);
            }
            return results;
          },

          adjacent: function(nodes) {
            for (var i = 0, results = [], node; node = nodes[i]; i++) {
              var next = this.nextElementSibling(node);
              if (next) results.push(next);
            }
            return results;
          },

          laterSibling: function(nodes) {
            var h = Selector.handlers;
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            h.concat(results, Element.nextSiblings(node));
            return results;
          },

          nextElementSibling: function(node) {
            while (node = node.nextSibling)
            if (node.nodeType == 1) return node;
            return null;
          },

          previousElementSibling: function(node) {
            while (node = node.previousSibling)
            if (node.nodeType == 1) return node;
            return null;
          },

    // TOKEN FUNCTIONS
          tagName: function(nodes, root, tagName, combinator) {
            var uTagName = tagName.toUpperCase();
            var results = [], h = Selector.handlers;
            if (nodes) {
              if (combinator) {
          // fastlane for ordinary descendant combinators
                if (combinator == "descendant") {
                  for (var i = 0, node; node = nodes[i]; i++)
                  h.concat(results, node.getElementsByTagName(tagName));
                  return results;
                } else nodes = this[combinator](nodes);
                if (tagName == "*") return nodes;
              }
              for (var i = 0, node; node = nodes[i]; i++)
              if (node.tagName.toUpperCase() === uTagName) results.push(node);
              return results;
            } else return root.getElementsByTagName(tagName);
          },

          id: function(nodes, root, id, combinator) {
            var targetNode = $(id), h = Selector.handlers;
            if (!targetNode) return [];
            if (!nodes && root == document) return [targetNode];
            if (nodes) {
              if (combinator) {
                if (combinator == 'child') {
                  for (var i = 0, node; node = nodes[i]; i++)
                  if (targetNode.parentNode == node) return [targetNode];
                } else if (combinator == 'descendant') {
                  for (var i = 0, node; node = nodes[i]; i++)
                  if (Element.descendantOf(targetNode, node)) return [targetNode];
                } else if (combinator == 'adjacent') {
                  for (var i = 0, node; node = nodes[i]; i++)
                  if (Selector.handlers.previousElementSibling(targetNode) == node)
                  return [targetNode];
                } else nodes = h[combinator](nodes);
              }
              for (var i = 0, node; node = nodes[i]; i++)
              if (node == targetNode) return [targetNode];
              return [];
            }
            return (targetNode && Element.descendantOf(targetNode, root)) ? [targetNode] : [];
          },

          className: function(nodes, root, className, combinator) {
            if (nodes && combinator) nodes = this[combinator](nodes);
            return Selector.handlers.byClassName(nodes, root, className);
          },

          byClassName: function(nodes, root, className) {
            if (!nodes) nodes = Selector.handlers.descendant([root]);
            var needle = ' ' + className + ' ';
            for (var i = 0, results = [], node, nodeClassName; node = nodes[i]; i++) {
              nodeClassName = node.className;
              if (nodeClassName.length == 0) continue;
              if (nodeClassName == className || (' ' + nodeClassName + ' ').include(needle))
              results.push(node);
            }
            return results;
          },

          attrPresence: function(nodes, root, attr, combinator) {
            if (!nodes) nodes = root.getElementsByTagName("*");
            if (nodes && combinator) nodes = this[combinator](nodes);
            var results = [];
            for (var i = 0, node; node = nodes[i]; i++)
            if (Element.hasAttribute(node, attr)) results.push(node);
            return results;
          },

          attr: function(nodes, root, attr, value, operator, combinator) {
            if (!nodes) nodes = root.getElementsByTagName("*");
            if (nodes && combinator) nodes = this[combinator](nodes);
            var handler = Selector.operators[operator], results = [];
            for (var i = 0, node; node = nodes[i]; i++) {
              var nodeValue = Element.readAttribute(node, attr);
              if (nodeValue === null) continue;
              if (handler(nodeValue, value)) results.push(node);
            }
            return results;
          },

          pseudo: function(nodes, name, value, root, combinator) {
            if (nodes && combinator) nodes = this[combinator](nodes);
            if (!nodes) nodes = root.getElementsByTagName("*");
            return Selector.pseudos[name](nodes, value, root);
          }
        },

        pseudos: {
          'first-child': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++) {
              if (Selector.handlers.previousElementSibling(node)) continue;
              results.push(node);
            }
            return results;
          },
          'last-child': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++) {
              if (Selector.handlers.nextElementSibling(node)) continue;
              results.push(node);
            }
            return results;
          },
          'only-child': function(nodes, value, root) {
            var h = Selector.handlers;
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            if (!h.previousElementSibling(node) && !h.nextElementSibling(node))
            results.push(node);
            return results;
          },
          'nth-child':        function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, formula, root);
          },
          'nth-last-child':   function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, formula, root, true);
          },
          'nth-of-type':      function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, formula, root, false, true);
          },
          'nth-last-of-type': function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, formula, root, true, true);
          },
          'first-of-type':    function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, "1", root, false, true);
          },
          'last-of-type':     function(nodes, formula, root) {
            return Selector.pseudos.nth(nodes, "1", root, true, true);
          },
          'only-of-type':     function(nodes, formula, root) {
            var p = Selector.pseudos;
            return p['last-of-type'](p['first-of-type'](nodes, formula, root), formula, root);
          },

    // handles the an+b logic
          getIndices: function(a, b, total) {
            if (a == 0) return b > 0 ? [b] : [];
            return $R(1, total).inject([], function(memo, i) {
              if (0 == (i - b) % a && (i - b) / a >= 0) memo.push(i);
              return memo;
            });
          },

    // handles nth(-last)-child, nth(-last)-of-type, and (first|last)-of-type
          nth: function(nodes, formula, root, reverse, ofType) {
            if (nodes.length == 0) return [];
            if (formula == 'even') formula = '2n+0';
            if (formula == 'odd')  formula = '2n+1';
            var h = Selector.handlers, results = [], indexed = [], m;
            h.mark(nodes);
            for (var i = 0, node; node = nodes[i]; i++) {
              if (!node.parentNode._countedByPrototype) {
                h.index(node.parentNode, reverse, ofType);
                indexed.push(node.parentNode);
              }
            }
            if (formula.match(/^\d+$/)) { // just a number
              formula = Number(formula);
              for (var i = 0, node; node = nodes[i]; i++)
              if (node.nodeIndex == formula) results.push(node);
            } else if (m = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
              if (m[1] == "-") m[1] = -1;
              var a = m[1] ? Number(m[1]) : 1;
              var b = m[2] ? Number(m[2]) : 0;
              var indices = Selector.pseudos.getIndices(a, b, nodes.length);
              for (var i = 0, node, l = indices.length; node = nodes[i]; i++) {
                for (var j = 0; j < l; j++)
                if (node.nodeIndex == indices[j]) results.push(node);
              }
            }
            h.unmark(nodes);
            h.unmark(indexed);
            return results;
          },

          'empty': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++) {
        // IE treats comments as element nodes
              if (node.tagName == '!' || node.firstChild) continue;
              results.push(node);
            }
            return results;
          },

          'not': function(nodes, selector, root) {
            var h = Selector.handlers, selectorType, m;
            var exclusions = new Selector(selector).findElements(root);
            h.mark(exclusions);
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            if (!node._countedByPrototype) results.push(node);
            h.unmark(exclusions);
            return results;
          },

          'enabled': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            if (!node.disabled && (!node.type || node.type !== 'hidden'))
            results.push(node);
            return results;
          },

          'disabled': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            if (node.disabled) results.push(node);
            return results;
          },

          'checked': function(nodes, value, root) {
            for (var i = 0, results = [], node; node = nodes[i]; i++)
            if (node.checked) results.push(node);
            return results;
          }
        },

        operators: {
          '=':  function(nv, v) { return nv == v; },
          '!=': function(nv, v) { return nv != v; },
          '^=': function(nv, v) { return nv == v || nv && nv.startsWith(v); },
          '$=': function(nv, v) { return nv == v || nv && nv.endsWith(v); },
          '*=': function(nv, v) { return nv == v || nv && nv.include(v); },
          '$=': function(nv, v) { return nv.endsWith(v); },
          '*=': function(nv, v) { return nv.include(v); },
          '~=': function(nv, v) { return (' ' + nv + ' ').include(' ' + v + ' '); },
          '|=': function(nv, v) { return ('-' + (nv || "").toUpperCase() +
            '-').include('-' + (v || "").toUpperCase() + '-'); }
        },

        split: function(expression) {
          var expressions = [];
          expression.scan(/(([\w#:.~>+()\s-]+|\*|\[.*?\])+)\s*(,|$)/, function(m) {
            expressions.push(m[1].strip());
          });
          return expressions;
        },

        matchElements: function(elements, expression) {
          var matches = $$(expression), h = Selector.handlers;
          h.mark(matches);
          for (var i = 0, results = [], element; element = elements[i]; i++)
          if (element._countedByPrototype) results.push(element);
          h.unmark(matches);
          return results;
        },

        findElement: function(elements, expression, index) {
          if (Object.isNumber(expression)) {
            index = expression; expression = false;
          }
          return Selector.matchElements(elements, expression || '*')[index || 0];
        },

        findChildElements: function(element, expressions) {
          expressions = Selector.split(expressions.join(','));
          var results = [], h = Selector.handlers;
          for (var i = 0, l = expressions.length, selector; i < l; i++) {
            selector = new Selector(expressions[i].strip());
            h.concat(results, selector.findElements(element));
          }
          return (l > 1) ? h.unique(results) : results;
        }
      });

      if (Prototype.Browser.IE) {
        Object.extend(Selector.handlers, {
    // IE returns comment nodes on getElementsByTagName("*").
    // Filter them out.
          concat: function(a, b) {
            for (var i = 0, node; node = b[i]; i++)
            if (node.tagName !== "!") a.push(node);
            return a;
          },

    // IE improperly serializes _countedByPrototype in (inner|outer)HTML.
          unmark: function(nodes) {
            for (var i = 0, node; node = nodes[i]; i++)
            node.removeAttribute('_countedByPrototype');
            return nodes;
          }
        });
      }

      function $$() {
        return Selector.findChildElements(document, $A(arguments));
      }
      var Form = {
        reset: function(form) {
          $(form).reset();
          return form;
        },

        serializeElements: function(elements, options) {
          if (typeof options != 'object') options = { hash: !!options };
          else if (Object.isUndefined(options.hash)) options.hash = true;
          var key, value, submitted = false, submit = options.submit;

          var data = elements.inject({ }, function(result, element) {
            if (!element.disabled && element.name) {
              key = element.name; value = $(element).getValue();
              if (value != null && element.type != 'file' && (element.type != 'submit' || (!submitted &&
              submit !== false && (!submit || key == submit) && (submitted = true)))) {
                if (key in result) {
            // a key is already present; construct an array of values
                  if (!Object.isArray(result[key])) result[key] = [result[key]];
                  result[key].push(value);
                }
                else result[key] = value;
              }
            }
            return result;
          });

          return options.hash ? data : Object.toQueryString(data);
        }
      };

      Form.Methods = {
        serialize: function(form, options) {
          return Form.serializeElements(Form.getElements(form), options);
        },

        getElements: function(form) {
          return $A($(form).getElementsByTagName('*')).inject([],
          function(elements, child) {
            if (Form.Element.Serializers[child.tagName.toLowerCase()])
            elements.push(Element.extend(child));
            return elements;
          }
    );
        },

        getInputs: function(form, typeName, name) {
          form = $(form);
          var inputs = form.getElementsByTagName('input');

          if (!typeName && !name) return $A(inputs).map(Element.extend);

          for (var i = 0, matchingInputs = [], length = inputs.length; i < length; i++) {
            var input = inputs[i];
            if ((typeName && input.type != typeName) || (name && input.name != name))
            continue;
            matchingInputs.push(Element.extend(input));
          }

          return matchingInputs;
        },

        disable: function(form) {
          form = $(form);
          Form.getElements(form).invoke('disable');
          return form;
        },

        enable: function(form) {
          form = $(form);
          Form.getElements(form).invoke('enable');
          return form;
        },

        findFirstElement: function(form) {
          var elements = $(form).getElements().findAll(function(element) {
            return 'hidden' != element.type && !element.disabled;
          });
          var firstByIndex = elements.findAll(function(element) {
            return element.hasAttribute('tabIndex') && element.tabIndex >= 0;
          }).sortBy(function(element) { return element.tabIndex }).first();

          return firstByIndex ? firstByIndex : elements.find(function(element) {
            return ['input', 'select', 'textarea'].include(element.tagName.toLowerCase());
          });
        },

        focusFirstElement: function(form) {
          form = $(form);
          form.findFirstElement().activate();
          return form;
        },

        request: function(form, options) {
          form = $(form), options = Object.clone(options || { });

          var params = options.parameters, action = form.readAttribute('action') || '';
          if (action.blank()) action = window.location.href;
          options.parameters = form.serialize(true);

          if (params) {
            if (Object.isString(params)) params = params.toQueryParams();
            Object.extend(options.parameters, params);
          }

          if (form.hasAttribute('method') && !options.method)
          options.method = form.method;

          return new Ajax.Request(action, options);
        }
      };

      /*--------------------------------------------------------------------------*/

      Form.Element = {
        focus: function(element) {
          $(element).focus();
          return element;
        },

        select: function(element) {
          $(element).select();
          return element;
        }
      };

      Form.Element.Methods = {
        serialize: function(element) {
          element = $(element);
          if (!element.disabled && element.name) {
            var value = element.getValue();
            if (value != undefined) {
              var pair = { };
              pair[element.name] = value;
              return Object.toQueryString(pair);
            }
          }
          return '';
        },

        getValue: function(element) {
          element = $(element);
          var method = element.tagName.toLowerCase();
          return Form.Element.Serializers[method](element);
        },

        setValue: function(element, value) {
          element = $(element);
          var method = element.tagName.toLowerCase();
          Form.Element.Serializers[method](element, value);
          return element;
        },

        clear: function(element) {
          $(element).value = '';
          return element;
        },

        present: function(element) {
          return $(element).value != '';
        },

        activate: function(element) {
          element = $(element);
          try {
            element.focus();
            if (element.select && (element.tagName.toLowerCase() != 'input' ||
            !['button', 'reset', 'submit'].include(element.type)))
            element.select();
          } catch (e) { }
          return element;
        },

        disable: function(element) {
          element = $(element);
          element.disabled = true;
          return element;
        },

        enable: function(element) {
          element = $(element);
          element.disabled = false;
          return element;
        }
      };

      /*--------------------------------------------------------------------------*/

      var Field = Form.Element;
      var $F = Form.Element.Methods.getValue;

      /*--------------------------------------------------------------------------*/

      Form.Element.Serializers = {
        input: function(element, value) {
          switch (element.type.toLowerCase()) {
            case 'checkbox':
            case 'radio':
                return Form.Element.Serializers.inputSelector(element, value);
            default:
                return Form.Element.Serializers.textarea(element, value);
          }
        },

        inputSelector: function(element, value) {
          if (Object.isUndefined(value)) return element.checked ? element.value : null;
          else element.checked = !!value;
        },

        textarea: function(element, value) {
          if (Object.isUndefined(value)) return element.value;
          else element.value = value;
        },

        select: function(element, value) {
          if (Object.isUndefined(value))
          return this[element.type == 'select-one' ?
          'selectOne' : 'selectMany'](element);
          else {
            var opt, currentValue, single = !Object.isArray(value);
            for (var i = 0, length = element.length; i < length; i++) {
              opt = element.options[i];
              currentValue = this.optionValue(opt);
              if (single) {
                if (currentValue == value) {
                  opt.selected = true;
                  return;
                }
              }
              else opt.selected = value.include(currentValue);
            }
          }
        },

        selectOne: function(element) {
          var index = element.selectedIndex;
          return index >= 0 ? this.optionValue(element.options[index]) : null;
        },

        selectMany: function(element) {
          var values, length = element.length;
          if (!length) return null;

          for (var i = 0, values = []; i < length; i++) {
            var opt = element.options[i];
            if (opt.selected) values.push(this.optionValue(opt));
          }
          return values;
        },

        optionValue: function(opt) {
    // extend element because hasAttribute may not be native
          return Element.extend(opt).hasAttribute('value') ? opt.value : opt.text;
        }
      };

      /*--------------------------------------------------------------------------*/

      Abstract.TimedObserver = Class.create(PeriodicalExecuter, {
        initialize: function($super, element, frequency, callback) {
          $super(callback, frequency);
          this.element   = $(element);
          this.lastValue = this.getValue();
        },

        execute: function() {
          var value = this.getValue();
          if (Object.isString(this.lastValue) && Object.isString(value) ?
          this.lastValue != value : String(this.lastValue) != String(value)) {
            this.callback(this.element, value);
            this.lastValue = value;
          }
        }
      });

      Form.Element.Observer = Class.create(Abstract.TimedObserver, {
        getValue: function() {
          return Form.Element.getValue(this.element);
        }
      });

      Form.Observer = Class.create(Abstract.TimedObserver, {
        getValue: function() {
          return Form.serialize(this.element);
        }
      });

      /*--------------------------------------------------------------------------*/

      Abstract.EventObserver = Class.create({
        initialize: function(element, callback) {
          this.element  = $(element);
          this.callback = callback;

          this.lastValue = this.getValue();
          if (this.element.tagName.toLowerCase() == 'form')
          this.registerFormCallbacks();
          else
            this.registerCallback(this.element);
        },

        onElementEvent: function() {
          var value = this.getValue();
          if (this.lastValue != value) {
            this.callback(this.element, value);
            this.lastValue = value;
          }
        },

        registerFormCallbacks: function() {
          Form.getElements(this.element).each(this.registerCallback, this);
        },

        registerCallback: function(element) {
          if (element.type) {
            switch (element.type.toLowerCase()) {
              case 'checkbox':
              case 'radio':
                  Event.observe(element, 'click', this.onElementEvent.bind(this));
              break;
              default:
                  Event.observe(element, 'change', this.onElementEvent.bind(this));
              break;
            }
          }
        }
      });

      Form.Element.EventObserver = Class.create(Abstract.EventObserver, {
        getValue: function() {
          return Form.Element.getValue(this.element);
        }
      });

      Form.EventObserver = Class.create(Abstract.EventObserver, {
        getValue: function() {
          return Form.serialize(this.element);
        }
      });
      if (!window.Event) var Event = { };

      Object.extend(Event, {
        KEY_BACKSPACE: 8,
        KEY_TAB:       9,
        KEY_RETURN:   13,
        KEY_ESC:      27,
        KEY_LEFT:     37,
        KEY_UP:       38,
        KEY_RIGHT:    39,
        KEY_DOWN:     40,
        KEY_DELETE:   46,
        KEY_HOME:     36,
        KEY_END:      35,
        KEY_PAGEUP:   33,
        KEY_PAGEDOWN: 34,
        KEY_INSERT:   45,

        cache: { },

        relatedTarget: function(event) {
          var element;
          switch(event.type) {
            case 'mouseover': element = event.fromElement; break;
            case 'mouseout':  element = event.toElement;   break;
            default: return null;
          }
          return Element.extend(element);
        }
      });

      Event.Methods = (function() {
        var isButton;

        if (Prototype.Browser.IE) {
          var buttonMap = { 0: 1, 1: 4, 2: 2 };
          isButton = function(event, code) {
            return event.button == buttonMap[code];
          };

        } else if (Prototype.Browser.WebKit) {
          isButton = function(event, code) {
            switch (code) {
              case 0: return event.which == 1 && !event.metaKey;
              case 1: return event.which == 1 && event.metaKey;
              default: return false;
            }
          };

        } else {
          isButton = function(event, code) {
            return event.which ? (event.which === code + 1) : (event.button === code);
          };
        }

        return {
          isLeftClick:   function(event) { return isButton(event, 0) },
          isMiddleClick: function(event) { return isButton(event, 1) },
          isRightClick:  function(event) { return isButton(event, 2) },

          element: function(event) {
            event = Event.extend(event);

            var node          = event.target,
            type          = event.type,
            currentTarget = event.currentTarget;

            if (currentTarget && currentTarget.tagName) {
        // Firefox screws up the "click" event when moving between radio buttons
        // via arrow keys. It also screws up the "load" and "error" events on images,
        // reporting the document as the target instead of the original image.
              if (type === 'load' || type === 'error' ||
              (type === 'click' && currentTarget.tagName.toLowerCase() === 'input'
              && currentTarget.type === 'radio'))
              node = currentTarget;
            }
            if (node.nodeType == Node.TEXT_NODE) node = node.parentNode;
            return Element.extend(node);
          },

          findElement: function(event, expression) {
            var element = Event.element(event);
            if (!expression) return element;
            var elements = [element].concat(element.ancestors());
            return Selector.findElement(elements, expression, 0);
          },

          pointer: function(event) {
            var docElement = document.documentElement,
            body = document.body || { scrollLeft: 0, scrollTop: 0 };
            return {
              x: event.pageX || (event.clientX +
                  (docElement.scrollLeft || body.scrollLeft) -
                  (docElement.clientLeft || 0)),
                  y: event.pageY || (event.clientY +
                      (docElement.scrollTop || body.scrollTop) -
                      (docElement.clientTop || 0))
            };
          },

          pointerX: function(event) { return Event.pointer(event).x },
          pointerY: function(event) { return Event.pointer(event).y },

          stop: function(event) {
            Event.extend(event);
            event.preventDefault();
            event.stopPropagation();
            event.stopped = true;
          }
        };
      })();

      Event.extend = (function() {
        var methods = Object.keys(Event.Methods).inject({ }, function(m, name) {
          m[name] = Event.Methods[name].methodize();
          return m;
        });

        if (Prototype.Browser.IE) {
          Object.extend(methods, {
            stopPropagation: function() { this.cancelBubble = true },
            preventDefault:  function() { this.returnValue = false },
            inspect: function() { return "[object Event]" }
          });

          return function(event) {
            if (!event) return false;
            if (event._extendedByPrototype) return event;

            event._extendedByPrototype = Prototype.emptyFunction;
            var pointer = Event.pointer(event);
            Object.extend(event, {
              target: event.srcElement,
              relatedTarget: Event.relatedTarget(event),
              pageX:  pointer.x,
              pageY:  pointer.y
            });
            return Object.extend(event, methods);
          };

        } else {
          Event.prototype = Event.prototype || document.createEvent("HTMLEvents")['__proto__'];
          Object.extend(Event.prototype, methods);
          return Prototype.K;
        }
      })();

      Object.extend(Event, (function() {
        var cache = Event.cache;

        function getEventID(element) {
          if (element._prototypeEventID) return element._prototypeEventID[0];
          arguments.callee.id = arguments.callee.id || 1;
          return element._prototypeEventID = [++arguments.callee.id];
        }

        function getDOMEventName(eventName) {
          if (eventName && eventName.include(':')) return "dataavailable";
          return eventName;
        }

        function getCacheForID(id) {
          return cache[id] = cache[id] || { };
        }

        function getWrappersForEventName(id, eventName) {
          var c = getCacheForID(id);
          return c[eventName] = c[eventName] || [];
        }

        function createWrapper(element, eventName, handler) {
          var id = getEventID(element);
          var c = getWrappersForEventName(id, eventName);
          if (c.pluck("handler").include(handler)) return false;

          var wrapper = function(event) {
            if (!Event || !Event.extend ||
            (event.eventName && event.eventName != eventName))
            return false;

            Event.extend(event);
            handler.call(element, event);
          };

          wrapper.handler = handler;
          c.push(wrapper);
          return wrapper;
        }

        function findWrapper(id, eventName, handler) {
          var c = getWrappersForEventName(id, eventName);
          return c.find(function(wrapper) { return wrapper.handler == handler });
        }

        function destroyWrapper(id, eventName, handler) {
          var c = getCacheForID(id);
          if (!c[eventName]) return false;
          c[eventName] = c[eventName].without(findWrapper(id, eventName, handler));
        }

        function destroyCache() {
          for (var id in cache)
          for (var eventName in cache[id])
          cache[id][eventName] = null;
        }


  // Internet Explorer needs to remove event handlers on page unload
  // in order to avoid memory leaks.
        if (window.attachEvent) {
          window.attachEvent("onunload", destroyCache);
        }

  // Safari has a dummy event handler on page unload so that it won't
  // use its bfcache. Safari <= 3.1 has an issue with restoring the "document"
  // object when page is returned to via the back button using its bfcache.
        if (Prototype.Browser.WebKit) {
          window.addEventListener('unload', Prototype.emptyFunction, false);
        }

        return {
          observe: function(element, eventName, handler) {
            element = $(element);
            var name = getDOMEventName(eventName);

            var wrapper = createWrapper(element, eventName, handler);
            if (!wrapper) return element;

            if (element.addEventListener) {
              element.addEventListener(name, wrapper, false);
            } else {
              element.attachEvent("on" + name, wrapper);
            }

            return element;
          },

          stopObserving: function(element, eventName, handler) {
            element = $(element);
            var id = getEventID(element), name = getDOMEventName(eventName);

            if (!handler && eventName) {
              getWrappersForEventName(id, eventName).each(function(wrapper) {
                element.stopObserving(eventName, wrapper.handler);
              });
              return element;

            } else if (!eventName) {
              Object.keys(getCacheForID(id)).each(function(eventName) {
                element.stopObserving(eventName);
              });
              return element;
            }

            var wrapper = findWrapper(id, eventName, handler);
            if (!wrapper) return element;

            if (element.removeEventListener) {
              element.removeEventListener(name, wrapper, false);
            } else {
              element.detachEvent("on" + name, wrapper);
            }

            destroyWrapper(id, eventName, handler);

            return element;
          },

          fire: function(element, eventName, memo) {
            element = $(element);
            if (element == document && document.createEvent && !element.dispatchEvent)
            element = document.documentElement;

            var event;
            if (document.createEvent) {
              event = document.createEvent("HTMLEvents");
              event.initEvent("dataavailable", true, true);
            } else {
              event = document.createEventObject();
              event.eventType = "ondataavailable";
            }

            event.eventName = eventName;
            event.memo = memo || { };

            if (document.createEvent) {
              element.dispatchEvent(event);
            } else {
              element.fireEvent(event.eventType, event);
            }

            return Event.extend(event);
          }
        };
      })());

      Object.extend(Event, Event.Methods);

      Element.addMethods({
        fire:          Event.fire,
        observe:       Event.observe,
        stopObserving: Event.stopObserving
      });

      Object.extend(document, {
        fire:          Element.Methods.fire.methodize(),
        observe:       Element.Methods.observe.methodize(),
        stopObserving: Element.Methods.stopObserving.methodize(),
        loaded:        false
      });

      (function() {
  /* Support for the DOMContentLoaded event is based on work by Dan Webb,
        Matthias Miller, Dean Edwards and John Resig. */

        var timer;

        function fireContentLoadedEvent() {
          if (document.loaded) return;
          if (timer) window.clearInterval(timer);
          document.fire("dom:loaded");
          document.loaded = true;
        }

        if (document.addEventListener) {
          if (Prototype.Browser.WebKit) {
            timer = window.setInterval(function() {
              if (/loaded|complete/.test(document.readyState))
              fireContentLoadedEvent();
            }, 0);

            Event.observe(window, "load", fireContentLoadedEvent);

          } else {
            document.addEventListener("DOMContentLoaded",
            fireContentLoadedEvent, false);
          }

        } else {
          document.write("<script id=__onDOMContentLoaded defer src=//:><\/script>");
          $("__onDOMContentLoaded").onreadystatechange = function() {
            if (this.readyState == "complete") {
              this.onreadystatechange = null;
              fireContentLoadedEvent();
            }
          };
        }
      })();
      /*------------------------------- DEPRECATED -------------------------------*/

      Hash.toQueryString = Object.toQueryString;

      var Toggle = { display: Element.toggle };

      Element.Methods.childOf = Element.Methods.descendantOf;

      var Insertion = {
        Before: function(element, content) {
          return Element.insert(element, {before:content});
        },

        Top: function(element, content) {
          return Element.insert(element, {top:content});
        },

        Bottom: function(element, content) {
          return Element.insert(element, {bottom:content});
        },

        After: function(element, content) {
          return Element.insert(element, {after:content});
        }
      };

      var $continue = new Error('"throw $continue" is deprecated, use "return" instead');

// This should be moved to script.aculo.us; notice the deprecated methods
// further below, that map to the newer Element methods.
      var Position = {
  // set to true if needed, warning: firefox performance problems
  // NOT neeeded for page scrolling, only if draggable contained in
  // scrollable elements
        includeScrollOffsets: false,

  // must be called before calling withinIncludingScrolloffset, every time the
  // page is scrolled
        prepare: function() {
          this.deltaX =  window.pageXOffset
              || document.documentElement.scrollLeft
              || document.body.scrollLeft
              || 0;
          this.deltaY =  window.pageYOffset
              || document.documentElement.scrollTop
              || document.body.scrollTop
              || 0;
        },

  // caches x/y coordinate pair to use with overlap
        within: function(element, x, y) {
          if (this.includeScrollOffsets)
          return this.withinIncludingScrolloffsets(element, x, y);
          this.xcomp = x;
          this.ycomp = y;
          this.offset = Element.cumulativeOffset(element);

          return (y >= this.offset[1] &&
              y <  this.offset[1] + element.offsetHeight &&
              x >= this.offset[0] &&
              x <  this.offset[0] + element.offsetWidth);
        },

        withinIncludingScrolloffsets: function(element, x, y) {
          var offsetcache = Element.cumulativeScrollOffset(element);

          this.xcomp = x + offsetcache[0] - this.deltaX;
          this.ycomp = y + offsetcache[1] - this.deltaY;
          this.offset = Element.cumulativeOffset(element);

          return (this.ycomp >= this.offset[1] &&
              this.ycomp <  this.offset[1] + element.offsetHeight &&
              this.xcomp >= this.offset[0] &&
              this.xcomp <  this.offset[0] + element.offsetWidth);
        },

  // within must be called directly before
        overlap: function(mode, element) {
          if (!mode) return 0;
          if (mode == 'vertical')
          return ((this.offset[1] + element.offsetHeight) - this.ycomp) /
          element.offsetHeight;
          if (mode == 'horizontal')
          return ((this.offset[0] + element.offsetWidth) - this.xcomp) /
          element.offsetWidth;
        },

  // Deprecation layer -- use newer Element methods now (1.5.2).

        cumulativeOffset: Element.Methods.cumulativeOffset,

        positionedOffset: Element.Methods.positionedOffset,

        absolutize: function(element) {
          Position.prepare();
          return Element.absolutize(element);
        },

        relativize: function(element) {
          Position.prepare();
          return Element.relativize(element);
        },

        realOffset: Element.Methods.cumulativeScrollOffset,

        offsetParent: Element.Methods.getOffsetParent,

        page: Element.Methods.viewportOffset,

        clone: function(source, target, options) {
          options = options || { };
          return Element.clonePosition(target, source, options);
        }
      };

      /*--------------------------------------------------------------------------*/

      if (!document.getElementsByClassName) document.getElementsByClassName = function(instanceMethods){
        function iter(name) {
          return name.blank() ? null : "[contains(concat(' ', @class, ' '), ' " + name + " ')]";
        }

        instanceMethods.getElementsByClassName = Prototype.BrowserFeatures.XPath ?
            function(element, className) {
          className = className.toString().strip();
          var cond = /\s/.test(className) ? $w(className).map(iter).join('') : iter(className);
          return cond ? document._getElementsByXPath('.//*' + cond, element) : [];
            } : function(element, className) {
              className = className.toString().strip();
              var elements = [], classNames = (/\s/.test(className) ? $w(className) : null);
              if (!classNames && !className) return elements;

              var nodes = $(element).getElementsByTagName('*');
              className = ' ' + className + ' ';

              for (var i = 0, child, cn; child = nodes[i]; i++) {
                if (child.className && (cn = ' ' + child.className + ' ') && (cn.include(className) ||
                (classNames && classNames.all(function(name) {
                  return !name.toString().blank() && cn.include(' ' + name + ' ');
                }))))
                    elements.push(Element.extend(child));
              }
              return elements;
            };

            return function(className, parentElement) {
              return $(parentElement || document.body).getElementsByClassName(className);
            };
      }(Element.Methods);

      /*--------------------------------------------------------------------------*/

      Element.ClassNames = Class.create();
      Element.ClassNames.prototype = {
        initialize: function(element) {
          this.element = $(element);
        },

        _each: function(iterator) {
          this.element.className.split(/\s+/).select(function(name) {
            return name.length > 0;
          })._each(iterator);
        },

        set: function(className) {
          this.element.className = className;
        },

        add: function(classNameToAdd) {
          if (this.include(classNameToAdd)) return;
          this.set($A(this).concat(classNameToAdd).join(' '));
        },

        remove: function(classNameToRemove) {
          if (!this.include(classNameToRemove)) return;
          this.set($A(this).without(classNameToRemove).join(' '));
        },

        toString: function() {
          return $A(this).join(' ');
        }
      };

      Object.extend(Element.ClassNames.prototype, Enumerable);

      /*--------------------------------------------------------------------------*/

      Element.addMethods();