<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap 实例</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.2/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.2/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h1>宽度 Utility</h1>
<p>使用 w-* 类（.w-25、.w-50、.w-75、.w-100、.mw-auto、.mw-100）设置元素的宽度：</p>
<div class="w-25 bg-warning">宽度 25%</div>
<div class="w-50 bg-warning">宽度 50%</div>
<div class="w-75 bg-warning">宽度 75%</div>
<div class="w-100 bg-warning">宽度 100%</div>
<div class="w-auto bg-warning">自动宽度</div>
<div class="mw-100 bg-warning">最大宽度 100%</div>
</div>
</body>
</html>