<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap 示例</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://www.w3schools.cn/lib/bootstrap/5.1.3/css/bootstrap.min.css" rel="stylesheet">
<script src="https://www.w3schools.cn/lib/bootstrap/5.1.3/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>下拉菜单</h2>
<p>.dropdown 类用于指示下拉菜单。</p>
<p>使用 .dropdown-menu 类实际构建下拉菜单。</p>
<p>要打开下拉菜单，请使用带有 .dropdown-toggle 和 data-toggle="dropdown" 类的按钮或链接。</p>
<div class="dropdown">
<button type="button" class="btn btn-primary dropdown-toggle" data-bs-toggle="dropdown">
下拉按钮
</button>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#">链接 1</a></li>
<li><a class="dropdown-item" href="#">链接 2</a></li>
<li><a class="dropdown-item" href="#">链接 3</a></li>
</ul>
</div>
</div>
</body>
</html>