feat: designed not found page

src/app/not-found.tsx

@@ -1,8 +1,20 @@
+import { Button } from "@/components/ui/button";
+import { HomeIcon } from "@radix-ui/react-icons";
 
 export default function NotFoundPage() {
   return (
-    <main className="flex min-h-screen flex-col items-center justify-start">
-      <h1>404</h1>
+    <main className="min-h-screen grid place-items-center">
+      <div className="flex flex-col justify-center items-center text-center">
+        <h1 className="animate-fade-in -translate-y-4 text-balance bg-gradient-to-br from-black from-30% to-black/40 bg-clip-text py-6 text-5xl font-semibold leading-none tracking-tighter text-transparent opacity-0 [--animation-delay:200ms] sm:text-6xl md:text-7xl lg:text-8xl dark:from-white dark:to-white/40">
+          Page Not Found!
+        </h1>
+        <a href="/"><Button
+          className="flex items-center justify-center  animate-fade-in -translate-y-4 gap-1 text-white opacity-0 ease-in-out [--animation-delay:600ms] font-medium dark:text-black"
+        >
+          <span>Back to Home</span>
+          <HomeIcon className="ml-1 size-4 transition-transform duration-300 ease-in-out group-hover:translate-x-1" />
+        </Button></a>
+      </div>
     </main>
   );
 }