Potential quick fix for Issue #215. The proper solution is to

redo the grid layout for the page so that its fully responsive.
It is only partial responsive. Did tests using Firefox developer tools.

netbox/templates/dcim/rack.html

@@ -154,17 +154,19 @@
             </div>
         </div>
 	</div>
-    <div class="col-md-3">
-        <div class="rack_header">
+    <div class="row col-md-6">
+       <div class="col-md-6 col-sm-6 col-xs-12">
+          <div class="rack_header">
             <h4>Front</h4>
-        </div>
-        {% include 'dcim/_rack_elevation.html' with primary_face=front_elevation secondary_face=rear_elevation face_id=0 %}
-    </div>
-    <div class="col-md-3">
+          </div>
+          {% include 'dcim/_rack_elevation.html' with primary_face=front_elevation secondary_face=rear_elevation face_id=0 %}
+      </div>
+      <div class="col-md-6 col-sm-6 col-xs-12">
         <div class="rack_header">
             <h4>Rear</h4>
         </div>
         {% include 'dcim/_rack_elevation.html' with primary_face=rear_elevation secondary_face=front_elevation face_id=1 %}
+      </div>
     </div>
 </div>
 {% endblock %}