_includes/footer.html

<footer class="site-footer">

  <div class="wrap">

    <h2 class="footer-heading">{{ site.title }}</h2>

    <div class="footer-col-1 column">
      <ul>
        <li>{{ site.title }}</li>
        <li><a href="mailto:{{ site.email }}">{{ site.email }}</a></li>
      </ul>
    </div>

    <div class="footer-col-2 column">
      <ul>
        {% if site.github_username %}<li>
          <a href="https://github.com/{{ site.github_username }}">
            <span class="icon github">
              <svg version="1.1" class="github-icon-svg" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
                 viewBox="0 0 16 16" enable-background="new 0 0 16 16" xml:space="preserve">
                <path fill-rule="evenodd" clip-rule="evenodd" fill="#C2C2C2" d="M7.999,0.431c-4.285,0-7.76,3.474-7.76,7.761
                c0,3.428,2.223,6.337,5.307,7.363c0.388,0.071,0.53-0.168,0.53-0.374c0-0.184-0.007-0.672-0.01-1.32
                c-2.159,0.469-2.614-1.04-2.614-1.04c-0.353-0.896-0.862-1.135-0.862-1.135c-0.705-0.481,0.053-0.472,0.053-0.472
                c0.779,0.055,1.189,0.8,1.189,0.8c0.692,1.186,1.816,0.843,2.258,0.645c0.071-0.502,0.271-0.843,0.493-1.037
                C4.86,11.425,3.049,10.76,3.049,7.786c0-0.847,0.302-1.54,0.799-2.082C3.768,5.507,3.501,4.718,3.924,3.65
                c0,0,0.652-0.209,2.134,0.796C6.677,4.273,7.34,4.187,8,4.184c0.659,0.003,1.323,0.089,1.943,0.261
                c1.482-1.004,2.132-0.796,2.132-0.796c0.423,1.068,0.157,1.857,0.077,2.054c0.497,0.542,0.798,1.235,0.798,2.082
                c0,2.981-1.814,3.637-3.543,3.829c0.279,0.24,0.527,0.713,0.527,1.437c0,1.037-0.01,1.874-0.01,2.129
                c0,0.208,0.14,0.449,0.534,0.373c3.081-1.028,5.302-3.935,5.302-7.362C15.76,3.906,12.285,0.431,7.999,0.431z"/>
              </svg>
            </span>
            <span class="username">{{ site.github_username }}</span>
          </a>
        </li>{% endif %}
        {% if site.twitter_username %}<li>
          <a href="https://twitter.com/{{ site.twitter_username }}">
            <span class="icon twitter">
              <svg version="1.1" class="twitter-icon-svg" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
                 viewBox="0 0 16 16" enable-background="new 0 0 16 16" xml:space="preserve">
                <path fill="#C2C2C2" d="M15.969,3.058c-0.586,0.26-1.217,0.436-1.878,0.515c0.675-0.405,1.194-1.045,1.438-1.809
                c-0.632,0.375-1.332,0.647-2.076,0.793c-0.596-0.636-1.446-1.033-2.387-1.033c-1.806,0-3.27,1.464-3.27,3.27
                c0,0.256,0.029,0.506,0.085,0.745C5.163,5.404,2.753,4.102,1.14,2.124C0.859,2.607,0.698,3.168,0.698,3.767
                c0,1.134,0.577,2.135,1.455,2.722C1.616,6.472,1.112,6.325,0.671,6.08c0,0.014,0,0.027,0,0.041c0,1.584,1.127,2.906,2.623,3.206
                C3.02,9.402,2.731,9.442,2.433,9.442c-0.211,0-0.416-0.021-0.615-0.059c0.416,1.299,1.624,2.245,3.055,2.271
                c-1.119,0.877-2.529,1.4-4.061,1.4c-0.264,0-0.524-0.015-0.78-0.046c1.447,0.928,3.166,1.469,5.013,1.469
                c6.015,0,9.304-4.983,9.304-9.304c0-0.142-0.003-0.283-0.009-0.423C14.976,4.29,15.531,3.714,15.969,3.058z"/>
              </svg>
            </span>
            <span class="username">{{ site.twitter_username }}</span>
          </a>
        </li>{% endif %}
      </ul>
    </div>

    <div class="footer-col-3 column">
      <p class="text">{{ site.description }}</p>
    </div>

  </div>

</footer>