div垂直居中
<style type="text/css">
<!--
* {margin:0;padding:0}
div {
width:500px;
height:500px;
border:1px solid #666;
overflow:hidden;
position:relative;
display:table-cell;
text-align:center;
vertical-align:middle
}
div p {
position:static;
+position:absolute;
top:50%
}
img {
position:static;
+position:relative;
top:-50%;left:-50%;
}
-->
</style>
<div><p><img src="http://www.google.com/intl/en/images/logo.gif" /></p></div>