<body><style>*{ margin:0; padding:0;}.header{ width:100%; background:blue; }.menu{ width:100%; background:gray; height:40px;}.center{ width:940px; margin:0 auto; height:100px; background:red; position:relative;}.left{ position:absolute; top:0; left:-420px; width:420px; height:160px; background:yellow;}.right{ position:absolute; top:0; right:-420px; width:420px; height:160px; background:yellow;}</style><div class="header"> <div class="center"> <div class="left"></div> <div class="right"></div> </div></div><div class="menu"></div></body>
好像只能把left跟right两个合成一个，做header的背景。。
