<li class="nav-item m-2">
    <a class="nav-link" href={{pathto('index')}}>Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item m-2">
    <a class="nav-link" href={{pathto('gallery')}}>Gallery <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item m-2">
    <a class="nav-link" href={{pathto('tutorial')}}>Tutorial <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item m-2">
    <a class="nav-link" href="https://github.com/pylbm/pylbm">Source <span class="sr-only">(current)</span></a>
</li>