/* ============================================================
   teacher-dashboard.css
   Android Material Design – Compact & Refined
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
    /* ----- Material Design Color Palette ----- */
    --md-primary: #1976D2;
    --md-primary-variant: #1565C0;
    --md-primary-light: #BBDEFB;
    --md-on-primary: #FFFFFF;
    --md-secondary: #0288D1;
    --md-success: #2E7D32;
    --md-success-light: #A5D6A7;
    --md-danger: #C62828;
    --md-danger-light: #EF9A9A;
    --md-warning: #F57C00;
    --md-warning-light: #FFE0B2;
    --md-bg: #F5F7FA;
    --md-surface: #FFFFFF;
    --md-text-primary: #212121;
    --md-text-secondary: #757575;
    --md-text-hint: #9E9E9E;
    --md-border: #E0E0E0;
    --md-shadow-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.08);
    --md-shadow-2: 0 3px 6px rgba(0,0,0,0.16), 0 1px 3px rgba(0,0,0,0.08);
    --md-shadow-3: 0 6px 12px rgba(0,0,0,0.20), 0 3px 6px rgba(0,0,0,0.08);
    --md-radius: 12px;
    --md-radius-sm: 6px;
    --md-radius-pill: 20px;
    --md-transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);

    /* Layout */
    --sidebar-width: 240px;
    --header-height: 56px;
    --bottom-nav-height: 56px;
}

/* ----- Dark Theme Variables ----- */
[data-theme="dark"] {
    --md-bg: #121212;
    --md-surface: #1E1E1E;
    --md-text-primary: #E0E0E0;
    --md-text-secondary: #AAAAAA;
    --md-text-hint: #777777;
    --md-border: #333333;
    --md-shadow-1: 0 1px 3px rgba(0,0,0,0.4);
    --md-shadow-2: 0 3px 6px rgba(0,0,0,0.5);
    --md-shadow-3: 0 6px 12px rgba(0,0,0,0.6);
    --md-primary-light: #1A3A5A;
    --md-success-light: #1A3A2A;
    --md-danger-light: #3A1A1A;
    --md-warning-light: #3A2A1A;
}

/* ----- Reset & Base ----- */
* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background: var(--md-bg);
    color: var(--md-text-primary);
    line-height: 1.4;
    -webkit-font-smoothing: antialiased;
    font-size: 14px;
}

.mcq-td-wrapper {
    max-width: 100%;
    min-height: 100vh;
    background: var(--md-bg);
}

/* ----- Header (App Bar) ----- */
.mcq-td-header {
    background: var(--md-surface);
    height: var(--header-height);
    padding: 0 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--md-border);
    position: sticky;
    top: 0;
    z-index: 500;
    box-shadow: var(--md-shadow-1);
}

.mcq-td-header h1 {
    font-size: 1.1rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--md-primary), var(--md-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin: 0;
}

.mcq-td-header p {
    font-size: 0.7rem;
    color: var(--md-text-secondary);
    margin: 0;
    font-weight: 500;
}

.header-actions {
    display: flex;
    gap: 6px;
    align-items: center;
}

/* ----- Layout (Desktop Sidebar + Content) ----- */
.mcq-dashboard-layout {
    display: flex;
    flex-direction: column;
    min-height: calc(100vh - var(--header-height));
}

.mcq-main-content {
    padding: 16px;
    flex: 1;
    animation: fadeIn 0.25s ease;
    padding-bottom: calc(var(--bottom-nav-height) + 16px);
}

.mcq-desktop-sidebar {
    display: none;
    background: var(--md-surface);
    border-right: 1px solid var(--md-border);
    width: var(--sidebar-width);
    height: calc(100vh - var(--header-height));
    position: sticky;
    top: var(--header-height);
    padding: 12px 12px 16px;
    overflow-y: auto;
    box-shadow: var(--md-shadow-1);
}

/* ----- Sidebar Navigation ----- */
.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.sidebar-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px;
    color: var(--md-text-secondary);
    text-decoration: none;
    border-radius: var(--md-radius-sm);
    font-weight: 500;
    font-size: 0.85rem;
    transition: background var(--md-transition);
}

.sidebar-item:hover { background: var(--md-bg); color: var(--md-primary); }
.sidebar-item.active {
    background: var(--md-primary-light);
    color: var(--md-primary);
}

.sidebar-icon {
    font-size: 18px;
    width: 18px;
    height: 18px;
}

.sidebar-divider {
    height: 1px;
    background: var(--md-border);
    margin: 8px 0;
}

.sidebar-badge {
    background: var(--md-danger);
    color: white;
    font-size: 0.65rem;
    padding: 1px 8px;
    border-radius: var(--md-radius-pill);
    margin-left: auto;
    font-weight: 600;
}

/* ----- Credits Card (Material) ----- */
.credits-card {
    background: linear-gradient(135deg, #1976D2 0%, #1A237E 100%);
    border-radius: var(--md-radius);
    padding: 16px;
    margin-bottom: 16px;
    color: white;
    box-shadow: var(--md-shadow-2);
    position: relative;
    overflow: hidden;
}

.credits-card::after {
    content: '';
    position: absolute;
    top: -40px;
    right: -40px;
    width: 120px;
    height: 120px;
    background: rgba(255,255,255,0.05);
    border-radius: 50%;
}

.credits-card h3 {
    margin: 0 0 12px 0;
    font-size: 0.9rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
    position: relative;
    z-index: 1;
}

.credits-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    position: relative;
    z-index: 1;
}

.credit-item {
    text-align: center;
    padding: 8px;
    background: rgba(255,255,255,0.10);
    backdrop-filter: blur(4px);
    border-radius: var(--md-radius-sm);
    border: 1px solid rgba(255,255,255,0.10);
}

.credit-icon {
    font-size: 16px;
    display: block;
    margin: 0 auto 2px;
    height: 16px;
    width: 16px;
}

.credit-value {
    font-size: 1.2rem;
    font-weight: 700;
    display: block;
}

.credit-label {
    font-size: 0.6rem;
    opacity: 0.8;
    font-weight: 500;
    letter-spacing: 0.3px;
}

/* ----- Section Headers ----- */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.section-header h2 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--md-text-primary);
    margin: 0;
}

/* ----- Cards (Course, Quiz, Request) ----- */
.courses-grid, .requests-grid {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.course-card, .quiz-card, .request-item {
    background: var(--md-surface);
    border-radius: var(--md-radius);
    padding: 16px;
    box-shadow: var(--md-shadow-1);
    border: 1px solid var(--md-border);
    transition: all var(--md-transition);
    position: relative;
    overflow: hidden;
}

.course-card:hover, .quiz-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--md-shadow-2);
    border-color: var(--md-primary-light);
}

/* Course accent line */
.course-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 3px;
    height: 100%;
    background: var(--md-primary);
    border-radius: 0 2px 2px 0;
}

.course-title, .quiz-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--md-text-primary);
    margin: 0 0 4px 0;
    line-height: 1.3;
}

.course-meta, .quiz-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    font-size: 0.75rem;
    color: var(--md-text-secondary);
    margin-bottom: 12px;
}

.course-meta-item {
    display: flex;
    align-items: center;
    gap: 3px;
}

.course-status {
    display: inline-block;
    padding: 2px 10px;
    border-radius: var(--md-radius-pill);
    font-size: 0.65rem;
    font-weight: 600;
    background: var(--md-success-light);
    color: var(--md-success);
}

.course-actions, .quiz-actions {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
    margin-top: 4px;
}

.quiz-actions {
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
}

/* ----- Request Item ----- */
.request-item {
    background: var(--md-surface);
}

.request-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 4px;
}

.request-student {
    font-weight: 600;
    color: var(--md-text-primary);
    font-size: 0.9rem;
}

.request-time {
    font-size: 0.65rem;
    color: var(--md-text-hint);
    background: var(--md-bg);
    padding: 2px 8px;
    border-radius: var(--md-radius-pill);
}

.request-course {
    color: var(--md-primary);
    font-weight: 500;
    font-size: 0.8rem;
    margin-bottom: 12px;
    display: block;
}

.request-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

/* ----- Buttons (Material Style) ----- */
.mcq-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 6px 14px;
    border-radius: var(--md-radius-sm);
    font-weight: 500;
    font-size: 0.75rem;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: all var(--md-transition);
    outline: none;
    font-family: inherit;
    box-shadow: var(--md-shadow-1);
    text-transform: uppercase;
    letter-spacing: 0.3px;
    position: relative;
    overflow: hidden;
}

.mcq-btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    transform: translate(-50%, -50%);
    transition: width 0.5s, height 0.5s;
}
.mcq-btn:active::after {
    width: 200px;
    height: 200px;
}

.mcq-btn-primary {
    background: var(--md-primary);
    color: var(--md-on-primary);
}
.mcq-btn-primary:hover { background: var(--md-primary-variant); }

.mcq-btn-success {
    background: var(--md-success);
    color: white;
}
.mcq-btn-success:hover { background: #1B5E20; }

.mcq-btn-danger {
    background: var(--md-danger);
    color: white;
}
.mcq-btn-danger:hover { background: #B71C1C; }

.mcq-btn-outline {
    background: transparent;
    border: 1px solid var(--md-border);
    color: var(--md-text-primary);
    box-shadow: none;
}
.mcq-btn-outline:hover {
    border-color: var(--md-primary);
    background: var(--md-primary-light);
    color: var(--md-primary);
}

.mcq-btn-small {
    padding: 4px 10px;
    font-size: 0.7rem;
    text-transform: none;
    letter-spacing: normal;
}

.mcq-btn-full { width: 100%; }

.desktop-only-btn { display: none; }

/* ----- Bottom Navigation (Android Style) ----- */
.mcq-mobile-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--md-surface);
    border-top: 1px solid var(--md-border);
    display: flex;
    justify-content: space-around;
    padding: 4px 0 calc(4px + env(safe-area-inset-bottom));
    z-index: 100;
    box-shadow: 0 -1px 8px rgba(0,0,0,0.06);
    height: var(--bottom-nav-height);
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: var(--md-text-secondary);
    font-size: 0.6rem;
    padding: 2px 8px;
    border-radius: var(--md-radius-sm);
    transition: all var(--md-transition);
    position: relative;
    min-width: 48px;
}

.nav-item .nav-icon {
    font-size: 20px;
    height: 20px;
    width: 20px;
    margin-bottom: 1px;
    transition: transform 0.2s;
}

.nav-item.active {
    color: var(--md-primary);
}
.nav-item.active .nav-icon {
    transform: translateY(-1px);
}
.nav-item.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    width: 16px;
    height: 2px;
    background: var(--md-primary);
    border-radius: 2px 2px 0 0;
}

.nav-badge {
    position: absolute;
    top: -2px;
    right: 2px;
    background: var(--md-danger);
    color: white;
    font-size: 0.55rem;
    padding: 1px 5px;
    border-radius: var(--md-radius-pill);
    min-width: 16px;
    text-align: center;
    font-weight: 600;
}

/* ----- Floating Action Button (FAB) ----- */
.fab {
    position: fixed;
    bottom: calc(var(--bottom-nav-height) + 12px);
    right: 16px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--md-primary);
    color: white;
    border: none;
    cursor: pointer;
    box-shadow: var(--md-shadow-3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    z-index: 99;
    transition: all var(--md-transition);
}
.fab:hover { transform: scale(1.05); }
.fab:active { transform: scale(0.92); }

/* ----- Notifications (Material Dropdown) ----- */
.notification-bell {
    position: relative;
    cursor: pointer;
    padding: 6px;
    border-radius: 50%;
    transition: background var(--md-transition);
}
.notification-bell:hover { background: var(--md-bg); }

.notification-dropdown {
    display: none;
    position: absolute;
    top: 42px;
    right: 0;
    width: 300px;
    max-width: 85vw;
    background: var(--md-surface);
    border-radius: var(--md-radius);
    box-shadow: var(--md-shadow-3);
    border: 1px solid var(--md-border);
    z-index: 1000;
    animation: slideUp 0.2s ease;
}

.notification-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--md-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.notification-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--md-text-primary);
    margin: 0;
}

.notification-clear {
    background: none;
    border: none;
    color: var(--md-primary);
    font-size: 0.75rem;
    cursor: pointer;
    font-weight: 500;
}

.notification-list {
    max-height: 350px;
    overflow-y: auto;
}

.notification-item {
    padding: 12px 16px;
    border-bottom: 1px solid var(--md-border);
    transition: background var(--md-transition);
    cursor: pointer;
    font-size: 0.85rem;
}
.notification-item:hover { background: var(--md-bg); }
.notification-item.unread { background: var(--md-primary-light); }

/* ----- Modals (Bottom Sheet on Mobile) ----- */
.mcq-modal-backdrop {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 16px;
}

.mcq-modal-content {
    background: var(--md-surface);
    width: 100%;
    max-width: 440px;
    border-radius: var(--md-radius);
    padding: 20px;
    position: relative;
    box-shadow: var(--md-shadow-3);
    animation: slideUp 0.25s ease;
    max-height: 90vh;
    overflow-y: auto;
}

.mcq-modal-close {
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: 20px;
    line-height: 1;
    color: var(--md-text-secondary);
    cursor: pointer;
    background: var(--md-bg);
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: background var(--md-transition);
}
.mcq-modal-close:hover { background: var(--md-border); }

.mcq-modal-title {
    margin: 0 0 16px 0;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--md-text-primary);
}

/* ----- Form Elements ----- */
.mcq-form-group { margin-bottom: 16px; }
.mcq-form-label {
    display: block;
    margin-bottom: 4px;
    font-weight: 500;
    color: var(--md-text-secondary);
    font-size: 0.8rem;
}

.mcq-form-input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--md-border);
    border-radius: var(--md-radius-sm);
    font-size: 0.95rem;
    color: var(--md-text-primary);
    background: var(--md-bg);
    transition: border var(--md-transition);
    font-family: inherit;
}
.mcq-form-input:focus {
    outline: none;
    border-color: var(--md-primary);
    box-shadow: 0 0 0 3px var(--md-primary-light);
}

.mcq-modal-actions {
    display: flex;
    gap: 10px;
    margin-top: 16px;
    justify-content: flex-end;
}

/* ----- Empty State ----- */
.empty-state {
    text-align: center;
    padding: 40px 16px;
    color: var(--md-text-secondary);
}
.empty-icon {
    font-size: 48px;
    margin-bottom: 12px;
    color: var(--md-text-hint);
    display: block;
    height: 48px;
    width: 48px;
    margin-left: auto;
    margin-right: auto;
}

/* ----- Utility Classes ----- */
.text-center { text-align: center; }
.text-muted { color: var(--md-text-secondary); }
.text-primary { color: var(--md-primary); }
.text-success { color: var(--md-success); }
.text-danger { color: var(--md-danger); }
.mb-0 { margin-bottom: 0 !important; }
.mb-1 { margin-bottom: 6px !important; }
.mb-2 { margin-bottom: 12px !important; }
.mb-3 { margin-bottom: 18px !important; }
.mt-2 { margin-top: 12px; }
.w-100 { width: 100%; }
.d-flex { display: flex; }
.justify-content-between { justify-content: space-between; }
.hidden { display: none !important; }

/* ----- Animations ----- */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ============================================================
   DESKTOP BREAKPOINT (≥1024px)
   ============================================================ */
@media (min-width: 1024px) {
    .mcq-dashboard-layout {
        flex-direction: row;
    }

    .mcq-desktop-sidebar {
        display: block;
    }

    .mcq-mobile-nav,
    .fab {
        display: none !important;
    }

    .mobile-only { display: none !important; }
    .desktop-only-btn { display: inline-flex !important; }

    .mcq-main-content {
        padding: 24px 32px 24px 24px;
        max-width: calc(100% - var(--sidebar-width));
    }

    /* Grid for cards – 2 columns on desktop */
    .courses-grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
    .requests-grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    /* Course actions – full width buttons */
    .course-actions {
        grid-template-columns: repeat(2, 1fr);
    }

    /* Quiz card horizontal layout */
    .quiz-card {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 14px 20px;
    }
    .quiz-card .quiz-title,
    .quiz-card .quiz-meta {
        margin: 0;
    }
    .quiz-actions {
        grid-template-columns: repeat(2, auto);
        margin-left: auto;
        gap: 8px;
    }

    .notification-dropdown {
        top: 40px;
        right: 0;
    }
}

/* ============================================================
   MOBILE ADJUSTMENTS (Bottom Sheet Modals)
   ============================================================ */
@media (max-width: 767px) {
    .mcq-modal-backdrop {
        align-items: flex-end;
        padding: 0;
    }
    .mcq-modal-content {
        border-radius: var(--md-radius) var(--md-radius) 0 0;
        padding-bottom: calc(20px + env(safe-area-inset-bottom));
        animation: slideUpBottom 0.25s ease;
    }
    @keyframes slideUpBottom {
        from { transform: translateY(100%); }
        to { transform: translateY(0); }
    }
    .mcq-modal-close {
        top: 10px;
        right: 10px;
    }
}

/* ============================================================
   DARK MODE (system preference fallback)
   ============================================================ */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --md-bg: #121212;
        --md-surface: #1E1E1E;
        --md-text-primary: #E0E0E0;
        --md-text-secondary: #AAAAAA;
        --md-text-hint: #777777;
        --md-border: #333333;
        --md-shadow-1: 0 1px 3px rgba(0,0,0,0.4);
        --md-shadow-2: 0 3px 6px rgba(0,0,0,0.5);
        --md-shadow-3: 0 6px 12px rgba(0,0,0,0.6);
        --md-primary-light: #1A3A5A;
        --md-success-light: #1A3A2A;
        --md-danger-light: #3A1A1A;
        --md-warning-light: #3A2A1A;
    }
}