diff --git a/gtk-3.0/apps/xfce.css b/gtk-3.0/apps/xfce.css
index 5135936..e2dd2d2 100644
--- a/gtk-3.0/apps/xfce.css
+++ b/gtk-3.0/apps/xfce.css
@@ -11,7 +11,7 @@ XfceHeading {
 
 .xfce4-panel .button {
     border-radius: 0;
-    padding: 1;
+    padding: 1px;
 }
 
 .xfce4-panel .button:active {