<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<title>Document</title>
<style type="text/css">
*{
margin: 0px;
padding: 0px;
}
.adbox{
width: 960px;
height: 335px;
margin: -335px auto 0;
}
.menubox{
width: 100%;
height: 50px;
background: #000;
}
.menu{
width: 960px;
height: 50px;
font-size: 14px;
color: #fff;
margin: 0 auto;
line-height: 50px;
font-weight: 700;
padding-left: 20px;
}
.con{
width:960px;
height: 500px;
background: #ccc;
margin: 0 auto;
}
body{
height: 5000px;
}
</style>
<script type="text/javascript" src="./jquery-1.7.2.min.js"></script>
<script type="text/javascript">
$(function(){
$(‘.adbox‘).animate({marginTop : 0},2000,function(){
setTimeout(function(){
$(‘.adbox‘).animate({marginTop : -335},2000);
},3000)
});
})
</script>
</head>
<body>
<div class="adbox"><img src="./images/ad.jpg" /></div>
<div class="menubox">
<div class="menu">首页</div>
</div>
<div class="con"></div>
</body>
</html>
原文：http://www.cnblogs.com/tianxuan/p/4836808.html