x
 
                                <!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>编程字典</title>
  <style>
    ul {
        list-style-type: none;
        margin: 0;
        padding: 0;
        overflow: hidden;
        border: 1px solid #e7e7e7;
        background-color: #f3f3f3;
    }
    li {
        float: left;
    }
    li a {
        display: block;
        color: #666;
        text-align: center;
        padding: 14px 16px;
        text-decoration: none;
    }
    li a:hover:not(.active) {
        background-color: #ddd;
    }
    li a.active {
        color: white;
        background-color: #4CAF50;
    }
  </style>
</head>
<body>
  <ul>
    <li><a class="active" href="#home">Home</a></li>
    <li><a href="#news">News</a></li>