<style>
*{ margin:0; padding:0; list-style:none;}
img{ border:0;}
.header{ width:100%; background:#11192c;}
.nav{ width:1000px; margin:0 auto; overflow:hidden;}
.nav ul li{ height:40px; line-height:40px; float: right; padding:10px 10px; margin:0px 5px;position:relative;}
.nav ul li a{ color:#8f8f8f; font-family:'Microsoft Yahei'; font-size:17px; float: right; text-decoration:none;}
.nav ul li a:hover{ color:#ffffff; text-decoration:none;}
.nav ul li span{ display:block; position:absolute; width:0px; height:0px; background:#ffffff; top:58px; left:50%;}
</style>
</head>
<body>
<!-- 代码begin -->
<div class="header">
<div class="nav">
<ul>
<li><a href='#'>1</a><span></span></li>
<li><a href='#'>2</a><span></span></li>
<li><a href='#'>3</a><span></span></li>
<li><a href='#'>4</a><span></span></li>
<li><a href='#'>5</a><span></span></li>
<li><a href='#'>6</a><span></span></li>
</ul>
</div>
</div>
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Student, what effect do you want to achieve? Can you post a picture? With so much code, do you have to have someone run it to understand your problem? Just ask the question, attach the picture, and explain the requirements. And the methods you have used, this is the fastest way to answer questions