diff --git a/static/css/learnocaml_main.css b/static/css/learnocaml_main.css
index 04c76c079..8ba9bb61a 100644
--- a/static/css/learnocaml_main.css
+++ b/static/css/learnocaml_main.css
@@ -210,7 +210,7 @@ body {
   }
   #learnocaml-main-loading {
     position: absolute;
-    top: 0; left: 360; right: 0; bottom: 0;
+    top: 0; left: 360px; right: 0; bottom: 0;
   }
 }
 /* Medium screen: one column w/ popup menu */