/* ===== Tablet (max-width: 1024px) ===== */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
    }

    .has-sidebar .main-content {
        margin-left: 0;
    }

    .bottom-nav {
        display: block;
    }

    .main-content {
        padding: 1.5rem;
        padding-bottom: 90px;
    }

    .category-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }
}

/* ===== Mobile (max-width: 768px) ===== */
@media (max-width: 768px) {
    .main-content {
        padding: 1rem;
        padding-bottom: 85px;
    }

    .page-header h2 {
        font-size: 1.4rem;
    }

    .dashboard-stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .flashcard-container {
        height: 280px;
    }

    .flashcard-question {
        font-size: 1.1rem;
    }

    .flashcard-answer {
        font-size: 1.2rem;
    }

    .quiz-options {
        grid-template-columns: 1fr;
    }

    .quiz-option {
        padding: 0.85rem 1rem;
    }

    .category-grid {
        grid-template-columns: 1fr;
    }

    .badge-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }

    .quiz-results-stats {
        flex-direction: column;
        gap: 1rem;
    }

    .filter-tabs {
        overflow-x: auto;
        flex-wrap: nowrap;
        padding-bottom: 0.5rem;
    }

    .filter-tab {
        white-space: nowrap;
        flex-shrink: 0;
    }

    .dashboard-top {
        flex-direction: column;
    }

    .modal {
        width: 95%;
        padding: 1.5rem;
    }

    .modal-actions {
        flex-direction: column;
    }

    .study-controls {
        flex-direction: column;
    }
}

/* ===== Small Mobile (max-width: 480px) ===== */
@media (max-width: 480px) {
    .main-content {
        padding: 0.75rem;
        padding-bottom: 80px;
    }

    .page-header h2 {
        font-size: 1.2rem;
    }

    .flashcard-container {
        height: 250px;
    }

    .flashcard-question {
        font-size: 1rem;
    }

    .flashcard-face {
        padding: 1.25rem;
    }

    .stat-value {
        font-size: 1.5rem;
    }

    .dashboard-stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 0.75rem;
    }

    .btn {
        padding: 0.65rem 1.25rem;
        font-size: 0.9rem;
    }

    .btn-lg {
        padding: 0.85rem 1.5rem;
        font-size: 1rem;
    }

    .activity-chart {
        height: 80px;
    }

    .toast {
        min-width: 240px;
        padding: 0.75rem 1rem;
    }
}