<p>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-square fa-stack-2x"></i>
       <i class="fa fa-twitter fa-stack-1x fa-inverse"></i>
     </span>
     Twitter Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-square fa-stack-2x"></i>
       <i class="fa fa-facebook-f fa-stack-1x fa-inverse"></i>
     </span>
     Facebook Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-square fa-stack-2x"></i>
       <i class="fa fa-github fa-stack-1x fa-inverse"></i>
     </span>
     GitHub Icon
   </a>
 </p>
 <p>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle fa-stack-2x"></i>
       <i class="fa fa-twitter fa-stack-1x fa-inverse"></i>
     </span>
     Twitter Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle fa-stack-2x"></i>
       <i class="fa fa-facebook-f fa-stack-1x fa-inverse"></i>
     </span>
     Facebook Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle fa-stack-2x"></i>
       <i class="fa fa-github fa-stack-1x fa-inverse"></i>
     </span>
     GitHub Icon
   </a>
 </p>
 <p>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle-o fa-stack-2x"></i>
       <i class="fa fa-twitter fa-stack-1x"></i>
     </span>
     Twitter Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle-o fa-stack-2x"></i>
       <i class="fa fa-facebook-f fa-stack-1x"></i>
     </span>
     Facebook Icon
   </a>
   <a href="#">
     <span class="fa-stack" aria-hidden="true">
       <i class="fa fa-circle-o fa-stack-2x"></i>
       <i class="fa fa-github fa-stack-1x"></i>
     </span>
     GitHub Icon
   </a>
 </p>