//findPos function is from http://www.quirksmode.org/js/findpos.html;
//where its workings are explained in more detail.
document.write("<style>div.popup{filter:Alpha(opacity=90);	position:static;	margin-top:20;	width:80;	border:solid 1px black;	padding:8px;	background-color:white;}div.popup a{font-size:12px;line-height:25px}div.popup a:hover{color:red}</style>");
function findPos(obj) {
	var curleft = curtop = 0;
	if (obj.offsetParent) {
		curleft = obj.offsetLeft
		curtop = obj.offsetTop
		while (obj = obj.offsetParent) {
			curleft += obj.offsetLeft
			curtop += obj.offsetTop
		}
	}
	return [curleft,curtop];
}

//Display a named <strong class="highlight">menu</strong>, at the position of another object
function display_menu(parent,named)
{
	//get the named <strong class="highlight">menu</strong>
	var menu_element = document.getElementById(named);
	//override the 'display:none;' style attribute
	menu_element.style.display = "";
	//get the placement of the element that invoked the <strong class="highlight">menu</strong>...
	var placement = findPos(parent);
	//...and put the <strong class="highlight">menu</strong> there
	menu_element.style.left = placement[0] + "px";
	menu_element.style.top =  placement[1] ;
}

//Hide a named <strong class="highlight">menu</strong>
function hide_menu(named)
{
	//get the named <strong class="highlight">menu</strong>
	var menu_element = document.getElementById(named);
	//hide it with a style attribute
	menu_element.style.display = "none";
}
 
        
  function hidem(e, obj)
  {
    /* e.relatedTarget：返回鼠标进入的另一个标签元素对象，在这里指内层div */
    var eleObj = e.relatedTarget ? e.relatedTarget : e.type == 'mouseout' ? e.toElement : e.fromElement;
    while(eleObj &amp;&amp; eleObj != obj)
        eleObj = eleObj.parentNode; /* 找到内层元素的根节点对象 */
    if(eleObj != obj) /* 如果不是我们需要的根节点对象，说明鼠标已经离开外层元素区域了 */
        obj.style.display='none';
  }