*{box-sizing:border-box}body{margin:0;font-family:Arial,Helvetica,sans-serif;background:#0f172a;color:#e2e8f0}.center{min-height:100vh;display:grid;place-items:center;padding:16px}.card{width:100%;max-width:420px;background:#111827;border:1px solid #334155;border-radius:12px;padding:20px}.title{margin:0 0 16px;font-size:22px}.field{display:flex;flex-direction:column;gap:6px;margin-bottom:12px}.card input{border:1px solid #475569;border-radius:8px;background:#0b1220;color:#e2e8f0;padding:10px 12px}.card button{width:100%;border:0;border-radius:8px;background:#2563eb;color:#fff;padding:10px 12px;cursor:pointer}.error{color:#fca5a5}.error,.ok{margin:8px 0}.ok{color:#86efac}