<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<style type="text/css">
*{margin:0;padding:0}
body{font:12px/1.5 arial}
a{display:block;width:100px;color:#333;text-decoration:none}
div{height:20px;border-bottom:1px solid #ddd;line-height:20px}
dl{position:relative;width:100px;margin-left:200px;background:#f00}
dd{display:none;position:absolute;top:20px;left:0;width:100px;background:#f00}
.hover dd{display:block}
</style>
</head>
<body>
<div>
<dl onmouseover="this.className='hover'" onmouseout="this.className=''">
<dt>
<a href="#">我的携程</a>
</dt>
<dd>
<a href="#">我的订单</a>
<a href="#">我的积分</a>
<a href="#">我的票券</a>
<a href="#">我的信息</a>
</dd>
</dl>
</div>
</body>
</html>