Update back.html

back.html

@@ -9,7 +9,7 @@
   width: 100%;
   padding-top: 100%; /* 16:9 Aspect Ratio (divide 9 by 16 = 0.5625) */
 }
-  .responsive-iframe {
+  .container iframe {
   position: absolute;
   top: 0;
   left: 0;