Remove custom theme required for old override

src/app/globals.css

@@ -1,8 +1,6 @@
 @import "tailwindcss";
 @import "tw-animate-css";
 
-/* @custom-variant dark (&:where(.dark, .dark *)); */
-
 @theme inline {
   --color-background: var(--background);
   --color-foreground: var(--foreground);