内含php代码，也就是说要装php哦
<head>
<style type="text/css">
#aaa{
height:350px;
width:150px;
background-color:#999;
}
#asdasd{
height:auto;
width:inherit;
}
</style>
</head>
<body>
<? $gao=300;$kuan=400 ?>
<div id="aaa">
<img id="asdasd" src="asd.jpg" style="padding-top:<? echo $aa=(350-$gao*(150/$kuan))/2; ?>px;"/>
</div>
<img src="asd.jpg" />
</body>