W3School TIY Editor
W3School 在线教程
改变方向
暗黑模式
运行代码
<!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> <style> span { display: inline-block; width: 70px; height: 70px; margin: 6px; background-color: #f9f9f9; } </style> </head> <body> <div class="container mt-3"> <h2>边框宽度</h2> <p>使用 .border-1 到 .border-5 来改变边框的宽度：</p> <span class="border border-1"></span> <span class="border border-2"></span> <span class="border border-3"></span> <span class="border border-4"></span> <span class="border border-5"></span> </div> </body> </html>