diff --git a/IPython/html/static/notebook/less/widgets.less b/IPython/html/static/notebook/less/widgets.less
index 39021e6..e310d30 100644
--- a/IPython/html/static/notebook/less/widgets.less
+++ b/IPython/html/static/notebook/less/widgets.less
@@ -223,17 +223,20 @@
 
 .widget-hbox-single {
     /* Single line horizontal widgets */
+    .widget-hbox();
     height : 30px;
+}
 
-    .widget-hbox();
+.widget-vbox {
+    /* Vertical widgets */ 
+    .widget-box();
+    .vbox();
 }
 
 .widget-vbox-single {
     /* For vertical slides */ 
+    .widget-vbox();
     width : 30px;
-
-    .widget-box();
-    .vbox();
 }
 
 .widget-modal {