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  <meta charset="UTF-8">
  <title>Bootstrap Button Example</title>
  <link rel="stylesheet" href="" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
  <div class="container">
    <section class="mb-5">
      <h1>Here are some buttons:</h1>
      <button class="btn">Default button</button>
      <button class="btn btn-primary">Primary button</button>
      <button class="btn btn-secondary">Secondary button</button>
      <button class="btn btn-success">Success button</button>
      <button class="btn btn-danger">Danger button</button>
      <button class="btn btn-warning">Warning button</button>
      <button class="btn btn-info">Info button</button>
      <button class="btn btn-light">Light button</button>
      <button class="btn btn-dark">Dark button</button>
      <button class="btn btn-link">Link button</button>
    <section class="mb-5">
      <h1>Here are some more buttons:</h1>
      <button class="btn btn-outline-primary">Primary button</button>
      <button class="btn btn-outline-secondary">Secondary button</button>
      <button class="btn btn-outline-success">Success button</button>
      <button class="btn btn-outline-danger">Danger button</button>
      <button class="btn btn-outline-warning">Warning button</button>
      <button class="btn btn-outline-info">Info button</button>
      <button class="btn btn-outline-light">Light button</button>
      <button class="btn btn-outline-dark">Dark button</button>
    <section class="mb-5">
      <h1>Here are some other elements styled as buttons:</h1>
      <input type="button" class="btn btn-primary" value="Primary Button">
      <a href="#" role="button" class="btn btn-success">Success button!</a>
      <input type="button" class="btn btn-warning" value="Warning Button">
      <a href="#" role="button" class="btn btn-danger">Danger button!</a>
    <section class="mb-5">
      <h1>Here are some buttons at different sizes:</h1>
      <button class="btn btn-primary btn-lg">Large button</button>
      <button class="btn btn-primary btn-sm">Small button</button>
    <section class="mb-5">
      <h1>Here's a block-level button</h1>
      <button class="btn btn-primary btn-block">Block-level button</button>