<center>
<div class="btn-group" role="group" aria-label="...">
    {% if prev %}
    <a class="btn btn-default" href="{{ prev.link|e }}">Prev Page</a>
    {% else %}
    <button type="button" class="btn btn-default disabled">Prev Page</button>
    {% endif %}

    {% if next %}
    <a class="btn btn-default" href="{{ next.link|e }}">Next Page</a>
    {% else %}
    <button type="button" class="btn btn-default disabled">Next Page</button>
    {% endif %}
</div>
</center>