.form-challenge { padding: 16px 20px; margin-block: 12px; border: 1px solid #d6e2db; border-radius: 16px; background: #f3f7f4; color: #233c30; animation: form-challenge-reveal .2s ease-out; }
.form-challenge[hidden] { display: none; }
.form-challenge .field { margin: 0; display: grid; gap: 8px; }
.form-challenge input[name="challenge_answer"] { width: 100%; max-width: 130px; }
@keyframes form-challenge-reveal { from { opacity: 0; transform: translateY(-6px); } to { opacity: 1; transform: translateY(0); } }
@media (prefers-reduced-motion: reduce) { .form-challenge { animation: none; } }