diff --git a/IPython/html/static/notebook/less/menubar.less b/IPython/html/static/notebook/less/menubar.less
index 512a4e8..c35cde1 100644
--- a/IPython/html/static/notebook/less/menubar.less
+++ b/IPython/html/static/notebook/less/menubar.less
@@ -35,9 +35,50 @@ ul#help_menu li a{
 
 // Make sub menus work in BS3.
 // Credit: http://www.bootply.com/86684
-.dropdown-submenu{position:relative;}
-.dropdown-submenu>.dropdown-menu{top:0;left:100%;margin-top:-6px;margin-left:-1px;-webkit-border-radius:0 6px 6px 6px;-moz-border-radius:0 6px 6px 6px;border-radius:0 6px 6px 6px;}
-.dropdown-submenu:hover>.dropdown-menu{display:block;}
-.dropdown-submenu>a:after{display:block;content:" ";float:right;width:0;height:0;border-color:transparent;border-style:solid;border-width:5px 0 5px 5px;border-left-color:#cccccc;margin-top:5px;margin-right:-10px;}
-.dropdown-submenu:hover>a:after{border-left-color:#ffffff;}
-.dropdown-submenu.pull-left{float:none;}.dropdown-submenu.pull-left>.dropdown-menu{left:-100%;margin-left:10px;-webkit-border-radius:6px 0 6px 6px;-moz-border-radius:6px 0 6px 6px;border-radius:6px 0 6px 6px;}
+.dropdown-submenu {
+    position: relative;
+}
+
+.dropdown-submenu>.dropdown-menu {
+    top: 0;
+    left: 100%;
+    margin-top: -6px;
+    margin-left: -1px;
+    -webkit-border-radius: 0 6px 6px 6px;
+    -moz-border-radius: 0 6px 6px 6px;
+    border-radius: 0 6px 6px 6px;
+}
+
+.dropdown-submenu:hover>.dropdown-menu {
+    display: block;
+}
+
+.dropdown-submenu>a:after {
+    display: block;
+    content: " ";
+    float: right;
+    width: 0;
+    height: 0;
+    border-color: transparent;
+    border-style: solid;
+    border-width: 5px 0 5px 5px;
+    border-left-color: #cccccc;
+    margin-top: 5px;
+    margin-right: -10px;
+}
+
+.dropdown-submenu:hover>a:after{
+    border-left-color: #ffffff;
+}
+
+.dropdown-submenu.pull-left {
+    float: none;
+}
+
+.dropdown-submenu.pull-left>.dropdown-menu {
+    left: -100%;
+    margin-left: 10px;
+    -webkit-border-radius: 6px 0 6px 6px;
+    -moz-border-radius: 6px 0 6px 6px;
+    border-radius: 6px 0 6px 6px;
+}