function showlayer(obj,divname,pos){
  var top=obj.offsetTop; 
  var left=obj.offsetLeft;
  var height=obj.offsetHeight; 
  while(obj=obj.offsetParent){ 
    left+=obj.offsetLeft; 
    top+=obj.offsetTop; 
  }
	divname.style.top=top+height;
	divname.style.left=left-pos;
	divname.style.display="";
}
function hidelayer(divname){
	divname.style.display="none";
}