Updated the normalise css.

sass/navigation/navbar/_navbar.scss

@@ -4,10 +4,6 @@
 // Navbar
 //
 // A simple method to get navigation links to appear in one line.
-//
-// Markup: navbar.twig
-//
-// Style guide: navigation.navbar
 
 .navbar,
 %navbar {
@@ -33,3 +29,21 @@
     }
   }
 }
+
+//
+// Drupal selectors.
+//
+
+.main-navigation {
+  // Hide the block titles put into the main-navigation area of the page.tpl.php.
+  .block-menu .block__title,
+  .block-menu-block .block__title {
+    @extend %visually-hidden;
+  }
+
+  // Main menu and secondary menu links and menu block links.
+  .links,
+  .menu {
+    @extend %navbar;
+  }
+}