var DropDownMenu = new Class({
 initialize: function(ul){
   var li = ul.getElements('li')
   var base = this
   this.i = 0
   this.li = new Array()
   li.each(function (li){
     li.addEvent('mouseover', function(){
       this.addClass('active')
     })
     li.addEvent('mouseout', function(){
       this.removeClass('active')
     })     
     var ul2 = li.getElement('ul')
     if(ul2) {
       base.li[base.i] = li
       base.i = base.i + 1 
     }
   })
   // li eventauslöser
   this.li.each(function (li){
    li.addEvent('mouseover', function(){
      this.getElement('ul').setStyle('display', 'block')
    })
    li.addEvent('mouseout', function(){
      this.getElement('ul').setStyle('display', 'none')
    })
   })
  }
});

window.addEvent('domready', function(){
  var ul = $('main_menu')
  if (ul) new DropDownMenu(ul)
});