dark mode fixes

scss/_dark.scss

 // stylelint-disable declaration-no-important
 
 @mixin dark-mode {
-  color: #afbdd1;
-  background: $dark;
+
+  &,
+  .modal-content,
+  .dropdown-menu {
+    background: $dark;
+    color: #afbdd1;
+  }
+
+  .dropdown-menu-arrow::after {
+    border-bottom-color: $dark;
+  }
 
   .card,
   .header,
@@ -10,7 +19,6 @@
   .sidenav,
   .topnav,
   .navbar,
-  .dropdown-menu,
   .form-control,
   .selectgroup-button {
     background: rgba(0, 0, 0, .1);

scss/ui/_dropdowns.scss

+.dropdown-divider {
+  border-color: $border-color;
+}
+
 .dropdown-menu-scrollable {
   height: auto;
   max-height: 12rem;
@@ -9,6 +13,10 @@
   box-shadow: $box-shadow;
 }
 
+.dropdown-item {
+  color: inherit;
+}
+
 .dropdown-menu-arrow {
   margin-top: .75rem;