#container{position:relative}.xxx{z-index:999;background-color:red;border-radius:50%;text-align:center;line-height:20px;width:20px;height:20px;cursor:pointer}#panel,.xxx{position:absolute;top:50px;right:10px}#panel{z-index:998;background-color:#fff;overflow-y:auto;width:400px;height:300px}