<style type="text/css">
        .box{
            width: 750px;
            margin: auto;
        }
        .img-box{
            width: 100%;
            position:relative;
            z-index:1;
        }
        .img-box img{
          
            left:0;
            right:0;
            width:100%;
            z-index: -1;
            *zoom:1;
        }
        .img-box:before {
            content: "";
            
            padding-bottom: 100%;
            width: 0.1px;    /*必须要有数值，否则无法把高度撑起来*/
            vertical-align: middle;
        }
    </style>
       <div class="box">
    <div class="img-box">
  {dede:field.body runphp=yes}
global $cfg_basehost;
$str = @me;
$search = '/(<img.*?)width=(["\'])?.*?(?(2)\2|\s)([^>]+>)/is';
$search1 = '/(<img.*?)height=(["\'])?.*?(?(2)\2|\s)([^>]+>)/is';
$search2 = '#(<img.*?style=".*?)width: \d+px;([^"]*?.*?>)#i';
$search3 = '#(<img.*?style=".*?)height: \d+px;([^"]*?.*?>)#i';
$content = preg_replace($search,'$1$3',$str);
$content = preg_replace($search1,'$1$3',$content);
$content = preg_replace($search2,'$1$2',$content);
$content = preg_replace($search3,'$1$2',$content);
@me = str_replace('/uploads/allimg/', $cfg_basehost.'/uploads/allimg/', $content);//手机版图片使用绝对路径
{/dede:field.body} 
    </div>
</div>