function setNav(activedIndex) {
  var nav = document.getElementById("nav");
  var lis = nav.getElementsByTagName("li");
  for (var i=0; i<lis.length; i++){
	lis.item(i).className = "closed";
  }
  if (activedIndex!=-1 && activedIndex!=null) {
	var node = lis.item(activedIndex);
	if (node.getElementsByTagName("li").length > 0){	  
	  node.className = "actived opened";
	} else {
	  node.className = "actived";
	}
	while (node.id != "nav") {
	  node = node.parentNode;
	  if (node.className == "closed"){
		node.className = "opened";
	  }
	}
  }
}