bootstrap with two buttons demo code example

Example 1: bootstrap 3 btn size

<button type="button" class="btn btn-primary btn-lg">Large button</button>
<button type="button" class="btn btn-secondary btn-lg">Large button</button>

<button type="button" class="btn btn-primary btn-sm">Small button</button>
<button type="button" class="btn btn-secondary btn-sm">Small button</button>

<button type="button" class="btn btn-primary btn-lg btn-block">Block level button</button>
<button type="button" class="btn btn-secondary btn-lg btn-block">Block level button</button>

Example 2: bootstrap button group

<div class="btn-toolbar" role="toolbar" aria-label="Toolbar with button groups">
  <div class="btn-group mr-2" role="group" aria-label="First group">
    <button type="button" class="btn btn-secondary">1</button>
    <button type="button" class="btn btn-secondary">2</button>
    <button type="button" class="btn btn-secondary">3</button>
    <button type="button" class="btn btn-secondary">4</button>
  </div>
  <div class="btn-group mr-2" role="group" aria-label="Second group">
    <button type="button" class="btn btn-secondary">5</button>
    <button type="button" class="btn btn-secondary">6</button>
    <button type="button" class="btn btn-secondary">7</button>
  </div>
  <div class="btn-group" role="group" aria-label="Third group">
    <button type="button" class="btn btn-secondary">8</button>
  </div>
</div>