css实现简单的下拉列表

 <div class="dropbox">
        <a href="#" class="list">
            菜单
        </a>
        <ul class="box">
            <li><a href="#">List 1</a></li>
            <li><a href="#">List 2</a></li>
            <li><a href="#">List 3</a></li>
            <li><a href="#">List 4</a></li>
            <li><a href="#">List 5</a></li>
        </ul>
    </div>

       *{
            padding: 0;
            margin: 0;
        }
        .dropbox{
            display: block;
        }
        .list{
            display: block;
            width: 80px;
            height: 30px;
            text-decoration: none;
            background-color: #929292;
            text-align: center;
            line-height: 30px;
            color: white;
        }
        .box{
            display: none;
            width: 70px;
            height: 100px; ;
        }
        .box li{
            list-style: none;
        }
        .box li a{
            text-decoration: none;
            display: block;
            width: 70px;
            height: 25px;
            background-color: darkgray;
            color: white;
            text-align: center;
            line-height: 25px;
        }
        .list:hover{
            background-color: #c40000;
        }
        .dropbox:hover .box{
            display: block;
        }
        .box li a:hover{
            background-color: #c40000;
        }