<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    <title>Template Bootstrap</title>
    <!-- File Bootstrap CSS -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css">
    <!-- CSS tùy chỉnh của bạn ở dưới này -->
</head>

<body>
    <h1>Xin chào Bootstrap!</h1>

    <!-- Code của bạn ở trên -->
    <!-- Các File JS:
        1: jQuery đầu tiên
        2: Sau đó Popper.js
        3: Cuối cùng là Bootstrap JS
    -->
    <script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/js/bootstrap.min.js"></script>
</body>

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