メガメニューコンポーネント

<nav class="bg-white dark:bg-gray-900 shadow-md">
  <div class="container mx-auto px-4 py-3 flex justify-between items-center">
    <div class="text-2xl font-bold text-gray-800 dark:text-white">ShopSwift</div>
    <div class="hidden md:flex space-x-6">
      <a href="#" class="text-gray-600 dark:text-gray-300 hover:text-orange-500 dark:hover:text-orange-400 transition duration-300">Home</a>
      <div class="relative group">
        <button class="text-gray-600 dark:text-gray-300 hover:text-orange-500 dark:hover:text-orange-400 transition duration-300">Categories</button>
        <div class="absolute left-0 mt-3 w-56 bg-white dark:bg-gray-800 shadow-lg rounded-md opacity-0 group-hover:opacity-100 group-hover:scale-100 transition-all duration-300 origin-top transform scale-95">
          <div class="p-4">
            <a href="#" class="block px-4 py-2 text-gray-800 dark:text-gray-200 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-md">Electronics</a>
            <a href="#" class="block px-4 py-2 text-gray-800 dark:text-gray-200 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-md">Apparel</a>
            <a href="#" class="block px-4 py-2 text-gray-800 dark:text-gray-200 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-md">Home Goods</a>
            <a href="#" class="block px-4 py-2 text-gray-800 dark:text-gray-200 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-md">Books</a>
          </div>
        </div>
      </div>
      <a href="#" class="text-gray-600 dark:text-gray-300 hover:text-orange-500 dark:hover:text-orange-400 transition duration-300">Deals</a>
      <a href="#" class="text-gray-600 dark:text-gray-300 hover:text-orange-500 dark:hover:text-orange-400 transition duration-300">Contact</a>
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    <div class="md:hidden">
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