.masterClass_wrapper{padding:30px 0}.masterClass_wrapper .btns_box>span{float:right}.masterClass_wrapper .main_con{margin-top:20px}.masterClass_wrapper .main_con .list_ul{width:300px;float:left;background-color:#fff;height:500px;border-radius:5px}.masterClass_wrapper .main_con .list_ul li{font-size:16px;padding:10px 15px;border-bottom:1px dashed #efefef;cursor:pointer}.masterClass_wrapper .main_con .list_ul li.on{border-left:3px solid #75ced1;background-color:rgba(117,206,209,.3);color:#75ced1}.masterClass_wrapper .main_con .video_box{width:880px;height:500px;border:1px solid #efefef;float:right;position:relative}.doubleplay{position:absolute;right:9px;top:12px}.doubleplay>a{color:#fafafa;padding:3px 20px;border-radius:2px;background:hsla(0,0%,42%,.9)}.doubleplay>ul{display:none;position:absolute;bottom:-152px;left:0;width:100%;text-align:center;color:#f0f0f0;background:rgba(49,49,49,.7);border-radius:0 0 2px 2px}.doubleplay>ul li{line-height:30px;font-size:14px;cursor:pointer}.doubleplay>ul li.on,.doubleplay>ul li:hover{color:#ff9f21}.doubleplay:hover a{background-color:rgba(49,49,49,.7);border-radius:2px 2px 0 0;color:#fff}.doubleplay:hover ul{display:block}