diff --git a/12/style.css b/12/style.css
index a1d0c87..7a878ca 100644
--- a/12/style.css
+++ b/12/style.css
@@ -442,7 +442,7 @@ a:hover{
   overflow: hidden;
 }
 
-#etherpad iframe {
+.etherpad_iframe {
   display: block;
   width: 100%;
   height: 100%;