diff --git a/IPython/html/static/notebook/js/notificationwidget.js b/IPython/html/static/notebook/js/notificationwidget.js
index 9bd5443..d4ed891 100644
--- a/IPython/html/static/notebook/js/notificationwidget.js
+++ b/IPython/html/static/notebook/js/notificationwidget.js
@@ -45,7 +45,7 @@ define([
         this.element.fadeIn(100);
 
         // reset previous set style
-        this.element.removeClass(),
+        this.element.removeClass();
         this.style();
         if (options.class){
 
diff --git a/IPython/html/static/notebook/less/notificationwidget.less b/IPython/html/static/notebook/less/notificationwidget.less
index 6a665dd..250a222 100644
--- a/IPython/html/static/notebook/less/notificationwidget.less
+++ b/IPython/html/static/notebook/less/notificationwidget.less
@@ -17,15 +17,15 @@
 }
 
 .notification_widget.warning {
-    .btn-warning()
+    .btn-warning();
 }
 .notification_widget.success {
-    .btn-success()
+    .btn-success();
 }
 .notification_widget.info {
-    .btn-info()
+    .btn-info();
 }
 .notification_widget.danger {
-    .btn-danger()
+    .btn-danger();
 }