feat: 404 page

app/not-found.tsx

@@ -0,0 +1,16 @@
+import { NavigateBack } from "@/components/common/NavigateBack";
+import Image from "next/image";
+
+export default function NotFound() {
+  return (
+    <div className="flex flex-col justify-center items-center gap-4 h-[480px]">
+      <Image
+        width={240}
+        height={120}
+        src="/404.jpg"
+        alt="pinkie pie: http error 404 page not found"
+      />
+      <NavigateBack />
+    </div>
+  );
+}

components/common/NavigateBack.tsx

@@ -0,0 +1,14 @@
+"use client";
+
+import { useRouter } from "next/navigation";
+import { Button } from "../ui/button";
+
+export function NavigateBack() {
+  const router = useRouter();
+
+  return (
+    <Button variant="secondary" onClick={() => router.back()}>
+      Go back
+    </Button>
+  );
+}