Rework the footer content.

user/themes/textbook/templates/partials/footer.html.twig

 <section id="footer" class="section bg-gray">
     <section class="container {{ grid_size }}">
-        <p><a href="https://m3p2.org">M3P2</a> was <i class="fa fa-code"></i> with <i class="fa fa-heart-o pulse"></i> by <a href="/authors" class="science"><i class="fa fa-flask"></i></a> and <a href="https://www.ljbac.com" class="ljbac"><i class="fa fa-cube"></i></a> with <a href="http://getgrav.org">Grav</a>.</p>
+        <p>
+            <i class="fa fa-code"></i>
+            with <i class="fa fa-heart-o pulse"></i>
+            by <a href="/authors" class="science"><i class="fa fa-flask"></i></a>
+            and <a href="https://www.ljbac.com" class="ljbac"><i class="fa fa-cube"></i></a>.
+        </p>
     </section>
 </section>