spotlight on ctrl+space, theme browser on ctrl+shift+up/down, no backdrop behind the theme list

src/apps/officer-web/Screens/Dashboard/Layout/Header/ThemeSwitcher.tsx

@@ -24,10 +24,10 @@ const {
  *
  * ── The overlay ──
  *
- * `ctrl+shift+space` opens a list in the middle of the screen; `j`/`k` move through it and `l` applies the
- * focused theme to the app BEHIND it. That is the whole idea, and it is why this is a portal over a
- * translucent backdrop rather than a modal dialog: you are meant to watch the application change while
- * you browse, so as little of it as possible should be covered.
+ * `ctrl+shift+↑/↓` opens a list in the middle of the screen; `j`/`k` move through it and `l` applies the
+ * focused theme to the app BEHIND it. That is the whole idea, and it is why this is a portal with no
+ * backdrop rather than a modal dialog: you are meant to watch the application change while you browse,
+ * so nothing of it should be covered.
  *
  * Ported from the owner's `vimazing`, keys and all.
  */
@@ -156,9 +156,9 @@ export const ThemeSwitcher = () => {
       {open &&
         createPortal(
           <div
+            // No backdrop at all — the whole point of the browse is watching the app change behind the
+            // list, so nothing may sit between them. The full-screen div stays for click-outside-to-close.
             className="fixed inset-0 z-[900] flex items-center justify-center"
-            // Deliberately light: the point is to see the app change behind it.
-            style={{ backgroundColor: 'color-mix(in srgb, var(--background) 55%, transparent)' }}
             onClick={() => setOpen(false)}
           >
             <div