Improve colors management

app/assets/stylesheets/color_themes/_color_theme_override_dark.scss

 // Only overriding existing selectors here, so disable some lint rules
 // scss-lint:disable IdSelector, SelectorFormat, NestingDepth, SelectorDepth, QualifyingElement
 body {
-  .navbar.navbar-fixed-top #user-menu .dropdown-menu > li > a {
-    color: $text-color;
-    &:hover { color: $white; }
-  }
-
   .publisher {
     form {
       #publisher_textarea_wrapper { background-color: $gray; }

app/assets/stylesheets/color_themes/dark/_style.scss

@@ -59,7 +59,8 @@ $dropdown-link-hover-color: $dropdown-link-color;
 
 //== Navbar
 $navbar-inverse-bg: $gray-darker;
-$navbar-inverse-link-hover-color: $text-color;
+$navbar-inverse-link-color: $gray-lighter;
+$navbar-inverse-link-hover-color: $white;
 $navbar-inverse-brand-hover-color: $navbar-inverse-link-hover-color;
 
 //== Tabs

app/assets/stylesheets/header.scss

@@ -175,13 +175,13 @@
       width: 100%;
 
       a {
-        color: #9d9d9d;
+        color: $navbar-inverse-link-color;
         font-weight: bold;
         padding: 10px 15px;
 
         &:hover {
-          background-color: transparent;
-          color: #fff;
+          background-color: $navbar-inverse-link-hover-bg;
+          color: $navbar-inverse-link-hover-color;
         }
       }
     }
@@ -215,12 +215,12 @@
       width: 100%;
 
       a {
-        color: $gray-light;
+        color: $navbar-inverse-link-color;
         padding-left: 55px;
 
         &:hover {
-          background-color: $brand-primary;
-          color: $gray-lighter;
+          background-color: $list-group-hover-bg;
+          color: $list-group-link-hover-color;
         }
       }