给层设置阴影
<style type="text/css">
.frame {position:relative; background-color:green;width:100px;height:100px;}
.shadow {float:left;background:#000; filter:progid:DXImageTransform.Microsoft.Blur(PixelRadius='5', MakeShadow='true', ShadowOpacity='0.60');}
</style>
<div class="shadow">
<div class="frame"></div>
</div>?
