diff --git a/plinth/modules/diagnostics/templates/diagnostics.html b/plinth/modules/diagnostics/templates/diagnostics.html
index c85203f08..d9d1908ee 100644
--- a/plinth/modules/diagnostics/templates/diagnostics.html
+++ b/plinth/modules/diagnostics/templates/diagnostics.html
@@ -24,7 +24,7 @@
 system to confirm that network services are running and configured
 properly. It may take a minute to complete.</p>
 
-<p><a class="btn btn-primary btn-large" href="{% url 'diagnostics:test' %}">
+<p><a class="btn btn-primary btn-lg" href="{% url 'diagnostics:test' %}">
   Run diagnostic test &raquo;
 </a></p>
 
diff --git a/plinth/modules/help/templates/about.html b/plinth/modules/help/templates/about.html
index 973751fcf..c2eaaf08e 100644
--- a/plinth/modules/help/templates/about.html
+++ b/plinth/modules/help/templates/about.html
@@ -38,9 +38,10 @@ runs on must be cheap. The software it runs on must be easy to
 install and administrate by anybody. It must be easy to
 transition from existing services.</p>
 
-<p><a class="btn btn-primary btn-large"
-href="http://wiki.debian.org/FreedomBox" target="_blank">Learn more
-&raquo;</a></p>
+<p>
+  <a class="btn btn-primary btn-lg" href="http://wiki.debian.org/FreedomBox"
+     target="_blank">Learn more&raquo;</a>
+</p>
 
 {% endblock %}