* {padding: 0;margin: 0;}
ul,li {list-style: none;}
.tab {overflow: hidden;}
.titleBox {float: left;width: 20%;background-color: #999999;height: 100%;position: relative;}
.titleList {margin: auto 0;position: relative;z-index: 2;}
.titleList li span{color: #333;padding: 20px;width: 80px;display: block;}
.current span{color: #fff !important;}
.contentBox {float: right;width: 80%;height: 100%;}
.contentList {background-color: #666666;}
.contentList li {height: 600px;}
.contentList li p {color: #fff;}
.backBox {background-color: #0d38f8;z-index:0;width: 120px;border-radius: 10px;margin-left: 5px;position: absolute;}
.backBox::before{content: "";position: absolute;width: 0px;height: 0px;border-left: 8px solid transparent;border-right: 8px solid transparent;border-bottom: 8px solid #fff;top: -15px;left: calc(50% - 8px);}
.backBox::after{content: "";position: absolute;width: 0px;height: 0px;border-left: 8px solid transparent;border-right: 8px solid transparent;border-top: 8px solid #fff;bottom: -15px;left: calc(50% - 8px);}
.backBox img {width: 16px;height: 16px;display: block;position: absolute;}
.backBox img:first-child{top: -20px;}
.backBox img:last-child{left: calc(50% - 8px);bottom: -20px;}