*{margin:0;padding:0}
ul,li{list-style:none}
ul{margin:50px}
ul li{float:left;width:120px;height:40px;line-height:40px;text-align:center;background:#37D5E6;border-right:1px solid #fff;color:#fff;    position: relative;cursor: pointer;}
div{position: absolute;width:300px;height:0;background:#F9A73F;top:40px;left:0;overflow: hidden;line-height:200px;transition: .3s;
-moz-transition:.3s;	/* Firefox 4 */
-webkit-transition:.3s;	/* Safari 和 Chrome */
-o-transition:.3s;	/* Opera */}
li:hover{background:#F9A73F}
li:hover div{
  height:200px;
}