.logo_img img {width: 86%; height: auto;}
.mb_bar {display: block;border: none;width: 40px;height: 40px;text-indent: -900em;overflow: hidden;position: absolute;top: 50px;right: 2%;cursor: pointer;outline: none;background: #525356 url(static/images/menu-button-bg.png) no-repeat center center;background-size: 50%;z-index: 99;border-radius: 5px;}
.nav ul li{width:25%;text-align:center;}
.nav ul li a{padding:0;}
.nav{display:none;position: absolute;z-index: 2;background: #fff;border-top: 1px solid #ddd;}
.index_focus{width:100%;height:200px; left:0;margin-left: 0;}
.index_focus img{width:100%;height:200px;}
.nav {margin-left: 0;margin-top: 10px;}