Bootstrap5 实例</title>

  <meta charset="utf-8">

  <meta name="viewport" content="width=device-width, initial-scale=1">

  <link href="https://cdn.staticfile.net/twitter-bootstrap/5.1.1/css/bootstrap.min.css" rel="stylesheet">

  <script src="https://cdn.staticfile.net/twitter-bootstrap/5.1.1/js/bootstrap.bundle.min.js"></script>

  <style>

  span {

    display: inline-block;

    width: 75px;

    height: 75px;

    margin: 6px;

    background-color: #f9f9f9;

  }

  </style>

​

​

​

<div class="container mt-3">

    <span class="border border-primary"></span>

    <span class="border border-secondary"></span>

    <span class="border border-success"></span>

    <span class="border border-danger"></span>

    <span class="border border-warning"></span>

    <span class="border border-info"></span>

    <span class="border border-light"></span>

    <span class="border border-dark"></span>

    <span class="border border-white"></span>

</div>

​

​

​