refactor: update button styles and text for improved consistency and theming

src/components/AddToCalendarButton.js

@@ -117,7 +117,7 @@ export default function AddToCalendarButton({
   return (
     <DropdownMenu open={isOpen} onOpenChange={setIsOpen}>
       <DropdownMenuTrigger asChild>
-        <Button variant={variant} size={size} className="gap-2">
+        <Button variant={variant} size={size} className="bg-[var(--purple-lavender)] text-white hover:bg-[var(--purple-muted)] rounded-full gap-2 dark:hover:bg-brand-lavender dark:hover:text-brand-dark-lavender">
           <Calendar className="h-4 w-4" />
           Add to Calendar
           <ChevronDown className="h-4 w-4" />