Hub: Use SASS color variables in theme, style secondary button, style…

… active item in dropdown (#2462)

* Hub: Use SASS color variables in theme, style secondary button, style active item in dropdown

sourcecode/hub/resources/css/theme.scss

@@ -1,16 +1,26 @@
 // The Edlib theme
 
 [data-bs-theme="edlib"] {
-    --bs-body-color: var(--bs-gray-700); //Default text color
-    --bs-border-color: var(--bs-gray-400); //Default border color for input, buttons, etc
+    --bs-body-color: #{$gray-700}; //Default text color
+    --bs-border-color: #{$gray-400}; //Default border color for input, buttons, etc
 
     // Primary button
     .btn-primary {
         @include button-variant($green-100, $gray-400, $gray-900, $green-200, $green-100, $gray-900);
     }
 
-    //Mobile / small screen nav bar
+    // Secondary button
+    .btn-secondary {
+        @include button-variant($white, $gray-400, $gray-900, $gray-200, $gray-400, $gray-900);
+    }
+
+    // Mobile / small screen nav bar
     .navbar-bottom {
         background-color: $green-200;
     }
+
+    .dropdown-menu {
+        --bs-dropdown-link-active-color: #{$gray-900};
+        --bs-dropdown-link-active-bg: #{$green-100};
+    }
 }