.material-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.material-card {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--border-radius-lg);
    padding: 1.25rem;
    position: relative;
    transition: var(--transition-base);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.material-card:hover {
    border-color: var(--primary-300);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.material-card.is-selected {
    border-color: var(--primary-500);
    background-color: var(--primary-50);
}

.material-card__header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.material-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: var(--font-size-xs);
    font-weight: 500;
}

.material-badge--digital {
    background-color: #eff6ff;
    color: #2563eb;
}

.material-badge--fisica {
    background-color: #fdf2f8;
    color: #db2777;
}

.material-badge--libro {
    background-color: #ecfdf5;
    color: #059669;
}

.material-checkbox {
    width: 1.25rem;
    height: 1.25rem;
    border-radius: 0.25rem;
    border: 2px solid var(--gray-300);
    appearance: none;
    cursor: pointer;
    position: relative;
    background-color: white;
    transition: var(--transition-base);
}

.material-checkbox:checked {
    background-color: var(--primary-500);
    border-color: var(--primary-500);
    background-image: url("data:image/svg+xml,%3csvg viewBox='0 0 16 16' fill='white' xmlns='http://www.w3.org/2000/svg'%3e%3cpath d='M12.207 4.793a1 1 0 010 1.414l-5 5a1 1 0 01-1.414 0l-2-2a1 1 0 011.414-1.414L6.5 9.086l4.293-4.293a1 1 0 011.414 0z'/%3e%3c/svg%3e");
}

.material-card__content h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 0.25rem;
}

.material-card__content p {
    font-size: var(--font-size-sm);
    color: var(--gray-500);
    margin: 0;
    line-height: 1.4;
}