function addEvent(elem,eventType,fn){
	if(!elem.addEventListener&&!elem.attachEvent){
		return false;
	}else if(elem.addEventListener){   
		elem.addEventListener(eventType,fn,false);
	}else if(elem.attachEvent){        
		elem.attachEvent("on"+eventType,fn);
	}
}

addEvent(window,"load",function(){
	function isMouseLeaveOrEnter(e,elem){
            e = e||window.event;
         
            if(e.type !="mouseout"&&e.type!="mouseover"){
                return false;
            }

            
            var reltg = e.relatedTarget?e.relatedTarget:e.type=="mouseout"?e.toElement:e.fromElement;
            while(reltg&&reltg!=elem){
                reltg = reltg.parentNode;
            }
            
            return (reltg!=elem);
        }
	
	var lis = document.getElementById("nav").getElementsByTagName("li");
	for(var i=0; i<lis.length; i++){
		lis[i].onmouseover=function(e){
			//alert("over");
		    if(isMouseLeaveOrEnter(e,this)){
			    this.className+=(this.className.length>0?" ":"") + "show";
			    if(this.getElementsByTagName("li").length>0){
				    this.getElementsByTagName("ul")[0].style.width = this.offsetWidth - 1 + "px";
				    this.getElementsByTagName("li")[this.getElementsByTagName("li").length-1].style.background = "none";
			    }
			 }
		}
		lis[i].onmouseout=function(e){
		    if(isMouseLeaveOrEnter(e,this)){
			    this.className=this.className.replace(new RegExp("( ?|^)show\\b"), "");
			  }
		}
	}
});