[FIX] website, *: force website UI dropdown style

* web_editor

The purpose is to force our dropdown style in our UI so that themes do
not break it anymore (same way all the other elements are forced (cards,
headings, etc)).

task-2059538

closes odoo/odoo#38321

X-original-commit: 4ef0eac5ba134f462f72f3e9c60e5c9fc95f3a8c
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>
Co-authored-by: qsm-odoo <qsm@odoo.com>

addons/web_editor/static/src/scss/web_editor.variables.scss

@@ -260,6 +260,24 @@ $o-we-toolbar-height: 32px;
     }
 }
 
+@mixin o-w-preserve-dropdown-menus {
+    .dropdown-menu {
+        background-color: white;
+    }
+    .dropdown-item {
+        color: #212529;
+
+        @include hover-focus {
+            color: darken(#212529, 5%);
+        }
+        &.active,
+        &:active {
+            color: white;
+            @include gradient-bg($o-brand-primary);
+        }
+    }
+}
+
 // Edition colors
 
 // Colors

addons/website/static/src/scss/website.ui.scss

@@ -15,6 +15,7 @@ body.o_connected_user {
 
 // MAIN MENU STYLE (added above navbar.scss)
 #oe_main_menu_navbar {
+    @include o-w-preserve-dropdown-menus;
     @include o-position-absolute(0, 0, auto, 0);
     position: fixed;
     z-index: $zindex-modal - 10;
@@ -97,6 +98,7 @@ body.o_connected_user {
 body .modal {
     &.o_technical_modal {
         @include o-w-preserve-base;
+        @include o-w-preserve-dropdown-menus;
         @include o-w-preserve-headings;
         @include o-w-preserve-forms;
         @include o-w-preserve-links;