1.Table的高度为100%，随屏幕变化而变化
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
<link href="common.css" rel="stylesheet" type="text/css" />
</head>
<body> <div style=" clear:both; height:100%; 100%;">
<table width="100%" height="100%" border="1">
<tr>
<td> </td>
<td width="980" valign="top"><table width="100%" height="100%" border="1">
<tr>
<td height="18">1258 </td>
</tr>
</table></td>
<td> </td>
</tr>
</table></div>
</body>
</html>