<!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-fluid mt-3">
<h1>Two Unequal Responsive Columns</h1>
<p>调整浏览器窗口大小可查看效果。</p>
<p>当屏幕宽度小于 576 像素时，列将自动堆叠在一起。</p>
<div class="row">
<div class="col-sm-4 p-3 bg-primary text-white">.col</div>
<div class="col-sm-8 p-3 bg-dark text-white">.col</div>
</div>
</div>
</body>
</html>