Changed SCSS rules due to changed navbar icon structure.

CHANGES.md

@@ -6,6 +6,7 @@ Changes
 
 ### Unreleased
 
+* 2017-12-05 - Changed SCSS rules due to changed navbar icon structure.
 * 2017-12-05 - Removed Font Awesome integration because it is now provided by core.
 * 2017-12-05 - Replaced the settings_link_page.mustache.original with the updated core version.
 * 2017-12-05 - Synchronized loginform.mustache with core changes.

scss/post.scss

@@ -95,20 +95,16 @@ body.loginbackgroundimage {
         header.navbar {
             background-color: $gray-dark;
 
-            .navbar-nav a.nav-link,
-            .nav-link,
+            .navbar-nav .nav-link .icon,
             .usertext,
             .dropdown-toggle {
                 color: #fff;
             }
-            .nav-link:hover,
+            .navbar-nav .nav-link .icon:hover,
             .usertext:hover,
             .dropdown-toggle:hover {
                 color: $brand-primary;
             }
-            .nav-link .icon {
-                filter: brightness(9);
-            }
         }
     }
 }