编程字典

源代码

<!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;
        background-color: #333;
    }

li {
        float: left;
    }

li a, .dropbtn {
        display: inline-block;
        color: white;
        text-align: center;
        padding: 14px 16px;
        text-decoration: none;
    }

li a:hover, .dropdown:hover .dropbtn {
        background-color: red;
    }

li.dropdown {
        display: inline-block;
    }

.dropdown-content {
        display: none;
        position: absolute;
        background-color: #f9f9f9;
        min-width: 160px;
        box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    }

.dropdown-content a {
        color: black;
        padding: 12px 16px;
        text-decoration: none;
        display: block;
        text-align: left;
    }

.dropdown-content a:hover {background-color: #f1f1f1}

.dropdown:hover .dropdown-content {
        display: block;
    }
  </style>
</head>
<body>

<ul>
    <li><a href="#home">Home</a></li>
    <li><a href="#news">News</a></li>
    <li class="dropdown">
      <a href="javascript:void(0)" class="dropbtn">Dropdown</a>
      <div class="dropdown-content">
        <a href="#">Link 1</a>
        <a href="#">Link 2</a>
        <a href="#">Link 3</a>
      </div>
    </li>
  </ul>

<h3>在导航栏的下拉菜单</h3>
  <p>鼠标经过 "Dropdown" 链接去查看下拉菜单.</p>

</body>
</html>

运行结果