ul, li, a怎么用

<style type="text/css">
*{margin:0; padding:0;font-size:14px}
body{padding-top:20px}
ul,li{list-style: none}
ul{background: yellow;}
li{float:left; width:60px; height:50px;}//width:60px后加,不然ie li会比a宽
a{display:inline-block;padding:0 30px;line-height: 50px;background:pink url(images/dian.jpg) no-repeat left center; width:60px;margin-left:30px;white-space:nowrap;overflow: hidden;}


/*外部div未设置高度, 清楚其内部div浮动产生脱离文档流*/
.clearfix:after {
    visibility: hidden;    
    display: block;
    font-size: 0;
    content: ".";
    clear: both;
    height: 0;
}
/*因为ie6、7不能识别伪类, 而只需要用zoom:1既能触发布局*/
* html .clearfix             {zoom: 1;} /*IE6*/
*:first-child+html .clearfix {zoom: 1;} /*IE7*/
</style>
</head>

<body>
    <ul class="clearfix">
        <li><a href="###">aaaaaaaaaaaaaaaaaaaaaaaa</a></li>
        <li><a href="###">b</a></li>
        <li><a href="###">ccc中中中</a></li>
    </ul>
</body>