body:before {content: "";position: fixed;top: -10px;left: 0;width: 100%;height: 10px;box-shadow: 0px 0px 10px rgba(0,0,0,.8);z-index: 100;
}

浏览器头部阴影不支持ie

 

.clearfix:after {clear: both;content: ".";display: block;height: 0;visibility: hidden;
}

清除浮动在父元素上使用

 

边框
border-radius: 2px 2px 2px 2px;
box-shadow: 1px 2px 5px #CCCCCC;
border: 1px solid #DDDDDD;