.nav{background:#65666D;height:40px;margin:0 auto;font-family:'Microsoft Yahei',"微软雅黑",arial,'宋体',sans-serif}.nav .nav-wrap{width:980px;margin:0 auto;position:relative}.nav .main-menu li{float:left;height:40px}.nav .main-menu a{position:relative;display:block;outline:0;float:left;color:#fff;font-size:16px;height:40px;line-height:42px;_line-height:44px\9;overflow:hidden;margin:0 auto;z-index:1000;zoom:1;padding:0 22px 0 23px;text-decoration:none;background:url(http://exp.bdstatic.com/static/common-jquery/widget/nav/img/line_75b3369.png) no-repeat 0 13px}.nav .main-menu a:visited{color:#fff}.nav .main-menu a:hover{background:#55575c;border-left:1px solid #4e5155;border-right:1px solid #4e5155;padding:0 22px;margin-right:-1px;z-index:1001}.nav .main-menu .current{z-index:1003}.nav .main-menu .current a{background:#4e5054;border-left:1px solid #3e4144;border-right:1px solid #3e4144;padding:0 22px;margin-right:-1px;z-index:1003}.nav .main-menu .current .dir-icon{background-position:-190px -130px}.nav .main-menu li.last{background:url(http://exp.bdstatic.com/static/common-jquery/widget/nav/img/line_75b3369.png) no-repeat right 13px}.nav .main-menu .all-category{position:relative}.nav .main-menu .all-category a{padding-right:35px}.nav .main-menu .all-category a:hover{padding-right:35px}.nav .main-menu .all-category a.all-category-hover{background:#55575c;border-left:1px solid #4e5155;border-right:1px solid #4e5155;position:relative;margin-right:-1px;z-index:1002;padding:0 35px 0 22px}.nav .main-menu .dir-icon{background:url(http://img.baidu.com/img/iknow/exp/global/nav-share.png) no-repeat -190px -134px;position:absolute;top:18px;left:62px;width:7px;height:4px;_overflow:hidden;cursor:pointer;z-index:1003;display:inline-block}.nav .main-menu .dir-icon-hover{background-position:-190px -130px}.nav .share-exp-e{display:block;height:40px;width:202px;float:right;background:url(http://img.baidu.com/img/iknow/exp/global/nav-share.png) no-repeat 0 0}.nav .share-exp-e:hover{background-position:0 -40px}.nav .share-exp-e:active{background-position:0 -80px}.nav .category-list{position:absolute;left:77px;top:40px;z-index:1100;width:195px;border:1px solid #999;border-top:0;background:#fcfcfc}.nav .category-list li{float:left;width:59px;padding:13px 0 0 25px;letter-spacing:1px}.nav .category-list li.first-line{padding-top:17px}.nav .category-list li.last-line{padding-bottom:17px}.nav .category-list li.even{padding-left:27px;padding-right:20px}.nav .category-list a:link,.nav .category-list a:visited{color:#2d64b3}