<h1 id="myHeader" onmouseover="dropshadow()" onmouseout="back()">请把鼠标移动到这个标题上</h1>
<html>
<head>
<style>
h1
{
color:black;
height:50;
font:bold;
}
</style>
<script type="text/javascript">
var i
function dropshadow()
i=0
interval=setInterval("makedropshadow()",10)
function back()
clearInterval(interval)
document.getElementById('myHeader').style.filter=false