.web_topics{height:580px;background:url(web_bg.jpg);width:960px;margin-left:auto;margin-right:auto;margin-top:-8px;margin-bottom:10px;}
.web_case{padding:100px 0 0 65px;}
.web_info{float:left;margin:115px 0 0 95px;width:500px;display:inline;}
.web_bottom{float:left;width:500px;margin:60px 0 0 70px;}