如何做个浮动的报表表头？？？------------给个提示就行

<style>
td{width:200px;height:200px;background-color:blue;}
div{overflow:scroll;background-color:red;width:100%;height:100%}
</style>
<body>
<table>
<tr><td style="height:25px">表头</td></tr>
<tr><td>
<div>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
AAAAA<br>
</div>
</td></tr>
</table>
</body>