templates/snippets/test_banner.html
{% if SHOW_TEST_WARNING %}
<div class="ribbon-box fade">
<div class="ribbon-wrapper">
<div class="ribbon"><h2>This is a <b>TEST</b> site</h2>
<p>Content may change or be removed without warning</p>
<button>OK</button>
</div>
</div>
</div>
{% endif %}