function navMenu(){  
	var about = document.getElementById("about");
	var service = document.getElementById("service");
	var technology = document.getElementById("technology");
	var contact = document.getElementById("contact");

 var menuArray=about.getElementsByTagName("li");
    for(var i=0;i<menuArray.length;i++) 
    {
     menuArray[i].onmouseover=navOver;
     menuArray[i].onmouseout=navOut;
    }
 var menu2Array=service.getElementsByTagName("li");
    for(var i=0;i<menu2Array.length;i++) 
    {
     menu2Array[i].onmouseover=navOver;
     menu2Array[i].onmouseout=navOut;
    }
 var menu3Array=technology.getElementsByTagName("li");
    for(var i=0;i<menu3Array.length;i++) 
    {
     menu3Array[i].onmouseover=navOver;
     menu3Array[i].onmouseout=navOut;
    }
 var menu4Array=contact.getElementsByTagName("li");
    for(var i=0;i<menu4Array.length;i++) 
    {
     menu4Array[i].onmouseover=navOver;
     menu4Array[i].onmouseout=navOut;
    }
}
function navOver(event)
{
 var event=event || window.event;
 var source = event.srcElement || event.target;
 source.style.background="#d1d1d1";
 source.style.font="700 12px Verdana, Arial, sans-serif";
 source.style.color="#5b5b5b";

}
function navOut(event)
{
 var event=event || window.event;
 var source = event.srcElement || event.target;
 source.style.background="#fff";
 source.style.font="400 12px Verdana, Arial, sans-serif";
}


function addLoadEvent(func){
 var oldonload = window.onload;
 if (typeof window.onload != "function"){
 window.onload = func;
 }else{
 window.onload = function(){
 oldonload();
 func();
   }
  }
}
addLoadEvent(navMenu);