/* ============================================================================
   EDULEARN - MAIN STYLESHEET
   Modern, minimal, professional design
   ============================================================================ */

/* ============================================================================
   CSS VARIABLES & THEME
   ============================================================================ */

:root {
    /* Colors */
    --primary-dark: #1e3a5f;
    --primary-blue: #2c4563;
    --primary-light: #3d5a7f;
    --accent-blue: #4a90e2;
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-700: #374151;
    --gray-900: #111827;
    --error: #dc2626;
    --success: #16a34a;
    --warning: #f59e0b;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --trans-fast: 150ms ease-in-out;
    --trans-base: 200ms ease-in-out;
    --trans-slow: 300ms ease-in-out;

    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
}

/* ============================================================================
   GLOBAL STYLES
   ============================================================================ */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--gray-900);
    background-color: var(--gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================================================
   AUTHENTICATION LAYOUT
   ============================================================================ */

.auth-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: var(--spacing-md);
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-blue) 100%);
}

.auth-wrapper {
    width: 100%;
    max-width: 420px;
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: var(--spacing-2xl);
}

/* Auth Header */
.auth-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.auth-logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 60px;
    height: 60px;
    border-radius: var(--radius-lg);
    background-color: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-blue) 100%);
    color: var(--accent-blue);
    margin-bottom: var(--spacing-md);
}

.auth-logo svg {
    color: var(--accent-blue);
}

.auth-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-sm);
}

.auth-subtitle {
    font-size: var(--font-size-sm);
    color: var(--gray-500);
}

/* Auth Form */
.auth-form {
    display: flex;
    flex-direction: column;
    margin-bottom: var(--spacing-xl);
}

.form-group {
    margin-bottom: var(--spacing-lg);
    display: flex;
    flex-direction: column;
}

.form-label {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: var(--spacing-sm);
    display: block;
}

.form-input {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: var(--font-size-base);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-md);
    background-color: var(--white);
    color: var(--gray-900);
    transition: all var(--trans-fast);
    font-family: inherit;
}

.form-input:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
    background-color: var(--white);
}

.form-input::placeholder {
    color: var(--gray-400);
}

.form-input-error {
    border-color: var(--error);
    background-color: rgba(220, 38, 38, 0.02);
}

.form-input-error:focus {
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.1);
}

.form-error {
    font-size: var(--font-size-xs);
    color: var(--error);
    margin-top: var(--spacing-xs);
    display: block;
}

.form-checkbox {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    font-size: var(--font-size-sm);
}

.form-checkbox input[type="checkbox"] {
    width: 16px;
    height: 16px;
    margin-right: var(--spacing-sm);
    cursor: pointer;
    accent-color: var(--accent-blue);
}

.form-checkbox label {
    cursor: pointer;
    color: var(--gray-600);
}

/* Buttons */
.btn {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: var(--font-size-base);
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--trans-fast);
    font-family: inherit;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn:focus {
    outline: none;
}

.btn-primary {
    background-color: var(--accent-blue);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background-color: #3b7ccf;
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.btn-block {
    width: 100%;
}

/* Demo Section */
.auth-demo {
    padding: var(--spacing-lg);
    background-color: var(--gray-50);
    border-radius: var(--radius-md);
    border: 1px solid var(--gray-200);
}

.demo-title {
    font-size: var(--font-size-xs);
    font-weight: 700;
    text-transform: uppercase;
    color: var(--gray-500);
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-md);
    display: block;
}

.demo-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
}

.demo-card {
    padding: var(--spacing-md);
    background-color: var(--white);
    border-radius: var(--radius-sm);
    border: 1px solid var(--gray-200);
}

.demo-label {
    display: block;
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--gray-600);
    margin-bottom: var(--spacing-xs);
}

.demo-card code {
    font-size: var(--font-size-xs);
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    color: var(--primary-blue);
    word-break: break-all;
}

/* ============================================================================
   RESPONSIVE DESIGN
   ============================================================================ */

@media (max-width: 640px) {
    .auth-wrapper {
        padding: var(--spacing-xl);
    }

    .auth-title {
        font-size: var(--font-size-xl);
    }

    .form-input {
        padding: var(--spacing-md);
        font-size: 16px; /* Prevent zoom on iOS */
    }

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

/* ============================================================================
   UTILITY CLASSES
   ============================================================================ */

.text-center {
    text-align: center;
}

.text-muted {
    color: var(--gray-500);
}

.text-error {
    color: var(--error);
}

.text-success {
    color: var(--success);
}

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

.p-1 { padding: var(--spacing-sm); }
.p-2 { padding: var(--spacing-md); }
.p-3 { padding: var(--spacing-lg); }
.p-4 { padding: var(--spacing-xl); }

/* ============================================================================
   MAIN CONTENT AREA
   ============================================================================ */

/* .main-content is defined in the sidebar section below */

/* ============================================================================
   PAGE HEADERS
   ============================================================================ */

.page-header {
    margin-bottom: var(--spacing-2xl);
}

.page-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-md);
}

.page-subtitle {
    font-size: var(--font-size-base);
    color: var(--gray-500);
}

/* ============================================================================
   CARDS & CONTAINERS
   ============================================================================ */

.card {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
    transition: all var(--trans-base);
}

.card:hover {
    box-shadow: var(--shadow-lg);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

.card-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--primary-dark);
}

/* ============================================================================
   GRID SYSTEM
   ============================================================================ */

.grid {
    display: grid;
    gap: var(--spacing-xl);
}

.grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

@media (max-width: 1024px) {
    .grid-cols-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .grid-cols-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 768px) {
    .grid-cols-4,
    .grid-cols-3,
    .grid-cols-2 {
        grid-template-columns: 1fr;
    }
}

/* ============================================================================
   STAT CARDS
   ============================================================================ */

.stat-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border-left: 4px solid var(--accent-blue);
    box-shadow: var(--shadow-sm);
    transition: all var(--trans-base);
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.stat-value {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-sm);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--gray-600);
}

/* ============================================================================
   COURSE CARDS
   ============================================================================ */

.course-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all var(--trans-base);
    cursor: pointer;
    display: flex;
    flex-direction: column;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.course-header {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-blue) 100%);
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 2.5rem;
}

.course-content {
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.course-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-sm);
}

.course-meta {
    display: flex;
    gap: var(--spacing-md);
    font-size: var(--font-size-xs);
    color: var(--gray-500);
    margin-bottom: var(--spacing-md);
}

.course-progress {
    margin-top: auto;
}

.progress-bar {
    height: 6px;
    background-color: var(--gray-200);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-blue) 0%, var(--primary-blue) 100%);
    transition: width 0.3s ease;
}

.progress-text {
    font-size: var(--font-size-xs);
    color: var(--gray-600);
    text-align: right;
}

/* ============================================================================
   TABLES
   ============================================================================ */

.table-responsive {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: var(--font-size-sm);
}

thead {
    background-color: var(--gray-50);
    border-bottom: 2px solid var(--gray-200);
}

th {
    padding: var(--spacing-md) var(--spacing-lg);
    text-align: left;
    font-weight: 600;
    color: var(--gray-700);
}

td {
    padding: var(--spacing-md) var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

tbody tr:hover {
    background-color: var(--gray-50);
}

/* ============================================================================
   BADGES & LABELS
   ============================================================================ */

.badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.badge-primary {
    background-color: rgba(74, 144, 226, 0.1);
    color: var(--accent-blue);
}

.badge-success {
    background-color: rgba(22, 163, 74, 0.1);
    color: var(--success);
}

.badge-warning {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning);
}

.badge-error {
    background-color: rgba(220, 38, 38, 0.1);
    color: var(--error);
}

/* ============================================================================
   DETAIL LIST (Show Pages)
   ============================================================================ */

.detail-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.detail-list > div {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

.detail-list > div:last-child {
    border-bottom: none;
}

.detail-list dt {
    font-weight: 600;
    color: var(--gray-700);
    min-width: 150px;
}

.detail-list dd {
    color: var(--gray-900);
    word-break: break-word;
}

.detail-list a {
    color: var(--accent-blue);
    text-decoration: none;
    font-weight: 600;
}

.detail-list a:hover {
    text-decoration: underline;
}

/* ============================================================================
   UTILITY CLASSES
   ============================================================================ */

.grid {
    display: grid;
}

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

.grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-cols-4 {
    grid-template-columns: repeat(4, 1fr);
}

.btn-block {
    width: 100%;
}

.btn-sm {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-xs);
}

@media (max-width: 768px) {
    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }
}

/* ============================================================================
   ADDITIONAL BUTTON VARIANTS
   ============================================================================ */

.btn-secondary {
    background-color: var(--white);
    color: var(--gray-700);
    border: 1px solid var(--gray-200);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
    background-color: var(--gray-50);
    border-color: var(--gray-300);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.btn-outline {
    background-color: transparent;
    color: var(--accent-blue);
    border: 1.5px solid var(--accent-blue);
}

.btn-outline:hover {
    background-color: var(--accent-blue);
    color: var(--white);
    transform: translateY(-1px);
}

.btn-danger {
    background-color: var(--error);
    color: var(--white);
    border: none;
    box-shadow: var(--shadow-sm);
}

.btn-danger:hover {
    background-color: #b91c1c;
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

/* Loading state */
.btn.loading {
    pointer-events: none;
    opacity: 0.75;
    position: relative;
}

.btn.loading::after {
    content: '';
    display: inline-block;
    width: 14px;
    height: 14px;
    border: 2px solid currentColor;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
    margin-left: var(--spacing-sm);
    vertical-align: middle;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================================================
   ALERT COMPONENTS (inline, non-toast)
   ============================================================================ */

.alert {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    border: 1px solid;
    font-size: var(--font-size-sm);
    font-weight: 500;
    line-height: 1.5;
}

.alert-success {
    background: #f0fdf4;
    border-color: #86efac;
    color: #166534;
}

.alert-error {
    background: #fef2f2;
    border-color: #fca5a5;
    color: #991b1b;
}

.alert-warning {
    background: #fffbeb;
    border-color: #fcd34d;
    color: #92400e;
}

.alert-info {
    background: #eff6ff;
    border-color: #93c5fd;
    color: #1e40af;
}

/* ============================================================================
   MOBILE RESPONSIVE NAVBAR HAMBURGER
   ============================================================================ */

.navbar-hamburger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 38px;
    height: 38px;
    background: var(--gray-100);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    padding: 8px;
    transition: background var(--trans-fast);
}

.navbar-hamburger:hover { background: var(--gray-200); }

.navbar-hamburger span {
    display: block;
    height: 2px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: all var(--trans-base);
}

.navbar-hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.navbar-hamburger.open span:nth-child(2) { opacity: 0; }
.navbar-hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.navbar-mobile-menu {
    display: none;
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow-md);
    z-index: 99;
    padding: var(--spacing-md);
    flex-direction: column;
    gap: 2px;
}

.navbar-mobile-menu.open { display: flex; }

.navbar-mobile-menu .nav-link {
    border-bottom: none;
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
}

.navbar-mobile-menu .nav-link.active {
    background: #eff6ff;
    color: var(--accent-blue);
    border-bottom: none;
}

@media (max-width: 768px) {
    .navbar-hamburger { display: flex; }
}

/* ============================================================================
   FORM IMPROVEMENTS
   ============================================================================ */

/* Prevent zoom on iOS for selects and textareas */
@media (max-width: 640px) {
    select.form-input,
    textarea.form-input {
        font-size: 16px;
    }
}

/* Consistent select appearance */
select.form-input {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%236b7280' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--spacing-md) center;
    padding-right: 2.5rem;
    cursor: pointer;
}

/* ============================================================================
   SIDEBAR LAYOUT — Vertical left navigation
   ============================================================================ */

:root {
    --sidebar-width: 240px;
    --sidebar-bg: #0f1729;
    --sidebar-border: rgba(255,255,255,.07);
    --sidebar-text: #94a3b8;
    --sidebar-text-hover: #f1f5f9;
    --sidebar-active-bg: rgba(99,102,241,.18);
    --sidebar-active-text: #a5b4fc;
    --sidebar-active-border: #6366f1;
    --topbar-height: 56px;
}

/* ── Body ──────────────────────────────────────────────────────────────────── */
.app-body {
    display: flex;
    min-height: 100vh;
    background: #f1f5f9;
}

/* ── Sidebar shell ─────────────────────────────────────────────────────────── */
.sidebar {
    position: fixed;
    top: 0; left: 0; bottom: 0;
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    display: flex;
    flex-direction: column;
    z-index: 200;
    transition: transform .25s ease;
    overflow-y: auto;
    overflow-x: hidden;
    scrollbar-width: none;
}
.sidebar::-webkit-scrollbar { display: none; }

/* ── Logo ──────────────────────────────────────────────────────────────────── */
.sidebar-logo {
    padding: 20px 16px 16px;
    flex-shrink: 0;
}
.sidebar-logo-link {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}
.sidebar-logo-icon {
    width: 36px; height: 36px;
    background: linear-gradient(135deg, #6366f1, #818cf8);
    border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(99,102,241,.4);
}
.sidebar-logo-name {
    font-size: .95rem;
    font-weight: 700;
    color: #f1f5f9;
    letter-spacing: .3px;
}

/* ── Divider ───────────────────────────────────────────────────────────────── */
.sidebar-divider {
    height: 1px;
    background: var(--sidebar-border);
    margin: 8px 16px;
    flex-shrink: 0;
}

/* ── User card ─────────────────────────────────────────────────────────────── */
.sidebar-user {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 16px;
    flex-shrink: 0;
}
.sidebar-user-avatar {
    width: 34px; height: 34px;
    border-radius: 50%;
    background: linear-gradient(135deg, #6366f1, #a78bfa);
    color: #fff;
    font-size: .75rem;
    font-weight: 700;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
}
.sidebar-user-info {
    display: flex;
    flex-direction: column;
    min-width: 0;
}
.sidebar-user-name {
    font-size: .8rem;
    font-weight: 600;
    color: #e2e8f0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.sidebar-user-role {
    font-size: .7rem;
    color: #64748b;
    margin-top: 1px;
}

/* ── Section label ─────────────────────────────────────────────────────────── */
.sidebar-section-label {
    font-size: .65rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: #475569;
    padding: 4px 20px 6px;
    flex-shrink: 0;
}

/* ── Nav ───────────────────────────────────────────────────────────────────── */
.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 2px;
    padding: 0 8px;
    flex-shrink: 0;
}
.sidebar-nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 12px;
    border-radius: 8px;
    text-decoration: none;
    color: var(--sidebar-text);
    font-size: .82rem;
    font-weight: 500;
    transition: background .15s, color .15s;
    position: relative;
    border-left: 2px solid transparent;
}
.sidebar-nav-item:hover {
    background: rgba(255,255,255,.06);
    color: var(--sidebar-text-hover);
}
.sidebar-nav-item.active {
    background: var(--sidebar-active-bg);
    color: var(--sidebar-active-text);
    border-left-color: var(--sidebar-active-border);
}
.sidebar-nav-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    opacity: .75;
}
.sidebar-nav-item:hover .sidebar-nav-icon,
.sidebar-nav-item.active .sidebar-nav-icon {
    opacity: 1;
}
.sidebar-nav-label {
    flex: 1;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* ── Sidebar collapsible group (students: Cours → TDs, TPE) ──────────────── */
.sidebar-group-toggle {
    background: none;
    border: none;
    width: 100%;
    cursor: pointer;
    text-align: left;
}
.sidebar-group-chevron {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    opacity: 0.5;
    transition: transform var(--trans-fast);
}
.sidebar-group.open .sidebar-group-chevron {
    transform: rotate(180deg);
    opacity: 0.8;
}
.sidebar-group-items {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
}
.sidebar-group.open .sidebar-group-items {
    max-height: 200px;
}
.sidebar-nav-sub {
    padding-left: calc(var(--spacing-lg) + 20px) !important;
}
.sidebar-nav-sub-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: currentColor;
    opacity: 0.4;
    flex-shrink: 0;
    margin-right: 4px;
}
.sidebar-nav-sub.active .sidebar-nav-sub-dot {
    opacity: 1;
    background: var(--accent-blue);
}

/* ── Badge ─────────────────────────────────────────────────────────────────── */
.sidebar-badge {
    background: #ef4444;
    color: #fff;
    font-size: .6rem;
    font-weight: 700;
    min-width: 18px;
    height: 18px;
    border-radius: 9px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 5px;
    flex-shrink: 0;
}

/* ── Footer / logout ───────────────────────────────────────────────────────── */
.sidebar-footer {
    padding: 0 8px 16px;
    flex-shrink: 0;
}
.sidebar-footer .sidebar-divider { margin: 0 8px 8px; }
.sidebar-logout {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 9px 12px;
    border: none;
    background: none;
    border-radius: 8px;
    color: var(--sidebar-text);
    font-size: .82rem;
    font-weight: 500;
    cursor: pointer;
    transition: background .15s, color .15s;
    text-align: left;
}
.sidebar-logout:hover {
    background: rgba(239,68,68,.12);
    color: #fca5a5;
}

/* ── Main area ─────────────────────────────────────────────────────────────── */
.app-main {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
}
.app-main.has-sidebar {
    margin-left: var(--sidebar-width);
}

/* ── Top bar (mobile only) ─────────────────────────────────────────────────── */
.topbar {
    display: none;
    align-items: center;
    gap: 12px;
    height: var(--topbar-height);
    padding: 0 16px;
    background: #fff;
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 100;
}
.topbar-hamburger {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px; height: 36px;
    background: none;
    border: none;
    cursor: pointer;
    border-radius: 8px;
    color: #374151;
    transition: background .15s;
}
.topbar-hamburger:hover { background: #f3f4f6; }
.topbar-title {
    flex: 1;
    font-size: .9rem;
    font-weight: 600;
    color: #111827;
}
.topbar-user {}
.topbar-avatar {
    width: 32px; height: 32px;
    border-radius: 50%;
    background: linear-gradient(135deg, #6366f1, #a78bfa);
    color: #fff;
    font-size: .72rem;
    font-weight: 700;
    display: flex; align-items: center; justify-content: center;
}

/* ── Sidebar overlay (mobile) ──────────────────────────────────────────────── */
.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.45);
    z-index: 199;
    opacity: 0;
    transition: opacity .25s;
}
.sidebar-overlay.active {
    opacity: 1;
}

/* ── Main content padding ──────────────────────────────────────────────────── */
.main-content {
    flex: 1;
    padding: 28px 32px;
    max-width: 1200px;
    width: 100%;
}

/* ── Responsive ────────────────────────────────────────────────────────────── */
@media (max-width: 900px) {
    .sidebar {
        transform: translateX(-100%);
        box-shadow: 4px 0 24px rgba(0,0,0,.25);
    }
    .sidebar.open {
        transform: translateX(0);
    }
    .sidebar-overlay {
        display: block;
    }
    .app-main.has-sidebar {
        margin-left: 0;
    }
    .topbar {
        display: flex;
    }
    .main-content {
        padding: 20px 16px;
    }
}

@media (min-width: 901px) {
    .topbar { display: none !important; }
}

/* ============================================================================
   SELECT2 CUSTOM THEME — matches EduLearn design system
   ============================================================================ */

.select2-container--default .select2-selection--single {
    height: 42px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md) !important;
    background: #fff;
    display: flex;
    align-items: center;
    transition: border-color .15s, box-shadow .15s;
}

.select2-container--default.select2-container--focus .select2-selection--single,
.select2-container--default.select2-container--open .select2-selection--single {
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(59,130,246,.15);
    outline: none;
}

.select2-container--default .select2-selection--single .select2-selection__rendered {
    color: var(--gray-700);
    font-size: var(--font-size-sm);
    line-height: 42px;
    padding-left: 12px;
    padding-right: 30px;
}

.select2-container--default .select2-selection--single .select2-selection__placeholder {
    color: var(--gray-400);
}

.select2-container--default .select2-selection--single .select2-selection__arrow {
    height: 40px;
    right: 6px;
}

.select2-container--default .select2-selection--single .select2-selection__arrow b {
    border-color: var(--gray-400) transparent transparent transparent;
}

.select2-container--default.select2-container--open .select2-selection--single .select2-selection__arrow b {
    border-color: transparent transparent var(--gray-400) transparent;
}

/* Clear button */
.select2-container--default .select2-selection--single .select2-selection__clear {
    color: var(--gray-400);
    font-size: 1rem;
    margin-right: 4px;
}
.select2-container--default .select2-selection--single .select2-selection__clear:hover {
    color: #dc2626;
}

/* Dropdown */
.select2-dropdown {
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md) !important;
    box-shadow: 0 8px 24px rgba(0,0,0,.1);
    overflow: hidden;
}

.select2-search--dropdown {
    padding: 8px;
    border-bottom: 1px solid var(--gray-100);
}

.select2-search--dropdown .select2-search__field {
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    padding: 6px 10px;
    font-size: var(--font-size-sm);
    color: var(--gray-700);
    width: 100%;
}

.select2-search--dropdown .select2-search__field:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 2px rgba(59,130,246,.15);
}

.select2-results__option {
    padding: 8px 12px;
    font-size: var(--font-size-sm);
    color: var(--gray-700);
    cursor: pointer;
    transition: background .1s;
}

.select2-container--default .select2-results__option--highlighted[aria-selected] {
    background: #eff6ff;
    color: var(--primary-dark);
}

.select2-container--default .select2-results__option[aria-selected="true"] {
    background: var(--accent-blue);
    color: #fff;
}

.select2-results__option--disabled {
    color: var(--gray-400) !important;
    cursor: default;
}

/* Error state */
.form-input-error + .select2-container .select2-selection--single {
    border-color: var(--error) !important;
}

/* Make select2 fill 100% width inside .form-group */
.form-group .select2-container {
    width: 100% !important;
}