//Email:lovelywsz@163.com
function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}
function change(id){
						for(var i=1;i<=3;i++) {
							document.getElementById("navmune"+i).className = "";
							document.getElementById("tab"+i).style.display = "none";
						}
						document.getElementById("navmune"+id).className = "specil";
						document.getElementById("tab"+id).style.display = "block";
					}	
					
function mychange(){
	var a=document.getElementById("classnav").getElementsByTagName("a");
	     for (var s=0;s<a.length;s++){
			 var sectionId=s+1;
			 a[s].destination = sectionId;
			 a[s].onclick=function(){
				change(this.destination);
				return false;}
			 }
	}
	
addLoadEvent(mychange);