yeti: style navbar dropdown on focus

yeti/bootstrap.css

@@ -7507,11 +7507,13 @@ td.visible-print {
   border: none;
 }
 
-.navbar .dropdown-menu > li > a {
+.navbar .dropdown-menu > li > a,
+.navbar .dropdown-menu > li > a:focus {
   padding: 12px 15px;
   font-size: 13px;
   font-weight: 300;
   color: #ffffff;
+  background-color: transparent;
 }
 
 .navbar .dropdown-menu > li > a:hover,

yeti/bootswatch.less

@@ -25,8 +25,10 @@
 		border: none;
 		background-color: @navbar-default-bg;
 
-		> li > a {
+		> li > a,
+		> li > a:focus {
 			padding: 12px 15px;
+			background-color: transparent;
 			font-size: 13px;
 			font-weight: 300;
 			color: @navbar-default-color;