Font-Awesome/src/_includes/examples/stacked.html

<section id="stacked">
  <h2 class="page-header">Stacked Icons</h2>
  <div class="row">
    <div class="col-md-3 col-sm-4">
      A method for easily stacking multiple icons. Use the <code>fa-icon-stack</code> class on the parent and
      <code>fa-icon-stack-base</code> for the bottom icon.
    </div>
    <div class="col-md-9 col-sm-8">
      <div class="well well-large well-transparent lead">
        <span class="fa-icon-stack">
          <i class="fa-icon fa-icon-unchecked fa-icon-stack-base"></i>
          <i class="fa-icon fa-icon-twitter"></i>
        </span>
        fa-icon-twitter on fa-icon-unchecked<br>
        <span class="fa-icon-stack">
          <i class="fa-icon fa-icon-circle fa-icon-stack-base"></i>
          <i class="fa-icon fa-icon-flag fa-icon-light"></i>
        </span>
        fa-icon-flag on fa-icon-circle<br>
        <span class="fa-icon-stack">
          <i class="fa-icon fa-icon-sign-blank fa-icon-stack-base"></i>
          <i class="fa-icon fa-icon-terminal fa-icon-light"></i>
        </span>
        fa-icon-terminal on fa-icon-sign-blank<br>
        <span class="fa-icon-stack">
          <i class="fa-icon fa-icon-camera"></i>
          <i class="fa-icon fa-icon-ban-circle fa-icon-stack-base text-danger"></i>
        </span>
        fa-icon-camera on fa-icon-ban-circle
      </div>
{% highlight html %}
<span class="fa-icon-stack">
  <i class="fa-icon fa-icon-unchecked fa-icon-stack-base"></i>
  <i class="fa-icon fa-icon-twitter"></i>
</span>
fa-icon-twitter on fa-icon-unchecked<br>
<span class="fa-icon-stack">
  <i class="fa-icon fa-icon-circle fa-icon-stack-base"></i>
  <i class="fa-icon fa-icon-flag fa-icon-light"></i>
</span>
fa-icon-flag on fa-icon-circle<br>
<span class="fa-icon-stack">
  <i class="fa-icon fa-icon-sign-blank fa-icon-stack-base"></i>
  <i class="fa-icon fa-icon-terminal fa-icon-light"></i>
</span>
fa-icon-terminal on fa-icon-sign-blank<br>
<span class="fa-icon-stack">
  <i class="fa-icon fa-icon-camera"></i>
  <i class="fa-icon fa-icon-ban-circle fa-icon-stack-base text-danger"></i>
</span>
fa-icon-camera on fa-icon-ban-circle
{% endhighlight %}
    </div>
  </div>
</section>