donate: Hide video link when there is no video

donate/templates/donate/donate_home_page.html

@@ -24,10 +24,14 @@
         </div><!-- /column -->
 
         <div class="col-12 col-lg-5 pl-xl-5 text-center">
+          {% image page.lead_preview width-500 as lead_preview %}
+          {% if page.lead_video %}
           <a data-fancybox="" href="{{ page.lead_video }}" title="Přehrát video">
-            {% image page.lead_preview width-500 as lead_preview %}
             <img class="img-fluid lazyload" data-src="{{ lead_preview.url }}" alt="Náhled videa">
           </a>
+          {% else %}
+          <img class="img-fluid lazyload" data-src="{{ lead_preview.url }}" alt="Náhled videa">
+          {% endif %}
         </div><!-- /column -->
 
       </div> <!-- /row -->