kit-ui/app/not-found.tsx

import Link from 'next/link';
import AnimatedBackground from '@/components/AnimatedBackground';
import Logo from '@/components/Logo';
import { ArrowLeft } from 'lucide-react';

export default function NotFound() {
  return (
    <main className="relative min-h-screen dark text-foreground flex flex-col">
      <AnimatedBackground />

      <div className="flex-1 flex flex-col items-center justify-center px-6 py-20 relative z-10 text-center">

        {/* Logo */}
        <Logo size={52} />

        {/* 404 */}
        <div
          className="mt-10"
          style={{ animation: 'slideUp 0.5s ease-out 0.15s both' }}
        >
          <span className="text-[80px] md:text-[120px] font-bold font-mono leading-none tabular-nums block bg-gradient-to-b from-foreground to-foreground/25 bg-clip-text text-transparent">
            404
          </span>
        </div>

        {/* Divider */}
        <div
          className="mt-6 w-12 h-px bg-gradient-to-r from-transparent via-primary/50 to-transparent"
          style={{ animation: 'fadeIn 0.5s ease-out 0.3s both' }}
        />

        {/* Message */}
        <div
          className="mt-6 space-y-2"
          style={{ animation: 'slideUp 0.5s ease-out 0.35s both' }}
        >
          <p className="text-sm font-medium text-foreground/70">Page not found</p>
          <p className="text-[11px] text-muted-foreground/45 font-mono max-w-xs mx-auto leading-relaxed">
            The tool or page you&apos;re looking for doesn&apos;t exist or has been moved.
          </p>
        </div>

        {/* CTA */}
        <div
          className="mt-8"
          style={{ animation: 'slideUp 0.5s ease-out 0.5s both' }}
        >
          <Link
            href="/"
            className="inline-flex items-center gap-2 px-5 py-2.5 glass rounded-xl border border-white/[0.06] hover:border-primary/40 hover:bg-primary/[0.07] text-sm font-medium text-foreground/60 hover:text-foreground transition-all duration-200"
          >
            <ArrowLeft className="w-3.5 h-3.5 text-primary" />
            Back to Home
          </Link>
        </div>
      </div>
    </main>
  );
}