.quiz-hero {
    background: linear-gradient(135deg, #0d9488 0%, #0f766e 100%);
}

.btn-teal {
    background-color: #0f766e;
    color: #fff;
    border-color: #0f766e;
}

.btn-teal:hover,
.btn-teal:focus {
    background-color: #0d5f58;
    border-color: #0d5f58;
    color: #fff;
}

.btn-outline-teal {
    border-color: #0f766e;
    color: #0f766e;
}

.btn-outline-teal:hover {
    background-color: #0f766e;
    color: #fff;
}

.play-btn {
    width: 3.1rem;
    height: 3.1rem;
    border-radius: 50%;
    font-size: 1.1rem;
    transition: transform .15s, box-shadow .15s;
}

.play-btn:hover {
    transform: scale(1.08);
}

.play-btn.playing {
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(13, 148, 136, .4); }
    50%      { box-shadow: 0 0 0 12px rgba(13, 148, 136, 0); }
}

.sound-option-btn.correct {
    border-color: #198754;
    background: #d1e7dd;
}

.sound-option-btn.incorrect {
    border-color: #dc3545;
    background: #f8d7da;
}