:root{color-scheme:light;font-family:Segoe UI,system-ui,-apple-system,sans-serif}body{margin:0;background:#f8fafc;color:#0f172a}.container{max-width:860px;margin:0 auto;padding:2rem 1rem;display:grid;gap:1rem}.card{display:grid;gap:.75rem;background:#fff;border:1px solid #e2e8f0;border-radius:12px;padding:1rem}input,button{font-size:1rem;padding:.75rem}button{border:0;border-radius:8px;background:#0f172a;color:#fff;cursor:pointer}.error{color:#b91c1c;font-weight:600}