div绝对居中、宽高自适应、多栏宽度自适应

     <style>
         body {
             background-color: #e1ddd9;
             font-size: 12px;
             font-family: Verdana, Arial, Helvetica, SunSans-Regular, Sans-Serif;
             color:#564b47;
             padding:0px;
             margin:0px;
         }
         #main {
             position:absolute;
             height:200px;
             width:400px;
             margin:-100px 0px 0px -200px;
             top: 50%;
             left: 50%;
             text-align: left;
             padding: 0px;
             background-color: #f5f5f5;
             border: 1px dotted #000000;
             overflow: auto;
         }
     </style>