#equation-display {
    text-align: center;
    margin: 2rem 0 0.5rem;
    font-size: 1.4rem;
    font-weight: 500;
    font-family: 'Georgia', serif;
    color: #333;
}

#amounts-display {
    text-align: center;
    margin: 0.5rem 0 1.5rem;
    font-size: 1.1rem;
    color: #495057;
}

.amount-item {
    display: inline-block;
    margin: 4px 12px;
    padding: 8px 16px;
    background: #f8f9fa;
    border-radius: 5px;
    font-family: 'Georgia', serif;
    font-weight: 500;
}

#primary-controls {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.reagent-btn {
    padding: 12px 28px;
    font-size: 1.15rem;
    font-family: 'Georgia', serif;
    min-width: 120px;
}

.reagent-btn.correct-choice {
    background-color: #28a745;
    color: white;
}

.reagent-btn.incorrect-choice {
    background-color: #dc3545;
    color: white;
}

.reagent-btn:disabled {
    opacity: 0.7;
}

#explanation-text {
    text-align: center;
    font-size: 0.95rem;
    color: #495057;
    margin: 0.5rem 0;
    min-height: 1.5em;
}