Fix header nav style

there is no ul.nav in the HTML.

library/less/_base.less

@@ -177,15 +177,17 @@ h5, .h5 {
 	#inner-header {}
 
 	#logo {}
-
+	
 	nav {
-		ul.nav {
-			li {
-				a {}
-
-				&:first-child {}
-
-				&:last-child {}
+		div.top-nav {
+			ul {
+				li {	
+					a {}
+	
+					&:first-child {}
+	
+					&:last-child {}
+				}
 			}
 		}
 	}