body{margin:0;padding:0;font-family:Segoe UI,sans-serif;background-color:#111827;color:#fff}h1,h2,h3{margin-bottom:1rem}input,button,select{font-size:1rem;padding:.75rem;margin-top:.5rem;margin-bottom:1rem;border-radius:6px;border:none;outline:none}input,select{width:100%;max-width:300px}button{background-color:#2563eb;color:#fff;cursor:pointer;transition:background-color .2s ease}button:hover{background-color:#1d4ed8}.container{padding:2rem;max-width:600px;margin:auto}.card{background-color:#1f2937;padding:2rem;border-radius:10px;box-shadow:0 0 20px #0000001a}.center{text-align:center}button.option{background-color:#f3f4f6;color:#111;font-weight:700;margin:.5rem;min-width:40px}button.option:hover{background-color:#e5e7eb}