/* CSS Variables for Theme */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #f59e0b;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --info: #3b82f6;
    --dark: #1e293b;
    --light: #f8fafc;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --gradient-secondary: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --radius-sm: 0.375rem;
    --radius: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

/* Layout */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.app-wrapper {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: var(--dark);
    color: white;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    transition: var(--transition);
    z-index: 1000;
}

.sidebar-header {
    padding: 1.5rem;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.sidebar-logo-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.sidebar-logo-text {
    font-size: 1.25rem;
    font-weight: 700;
}

.sidebar-nav {
    padding: 1rem 0;
}

.nav-section {
    padding: 0.5rem 1.5rem;
    margin-top: 1rem;
}

.nav-section-title {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--gray-500);
    margin-bottom: 0.5rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1.5rem;
    color: var(--gray-400);
    transition: var(--transition);
    cursor: pointer;
    border-left: 3px solid transparent;
}

.nav-item:hover {
    background: rgba(255,255,255,0.05);
    color: white;
}

.nav-item.active {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-light);
    border-left-color: var(--primary);
}

.nav-item i {
    width: 20px;
    font-size: 1.1rem;
}

.sidebar-footer {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 1rem 1.5rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    background: var(--gray-900);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.user-avatar {
    width: 40px;
    height: 40px;
    background: var(--gradient-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
}

.user-details {
    flex: 1;
}

.user-name {
    font-weight: 600;
    font-size: 0.9rem;
}

.user-role {
    font-size: 0.75rem;
    color: var(--gray-500);
    text-transform: capitalize;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 280px;
    min-height: 100vh;
}

/* Header */
.header {
    background: white;
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--gray-600);
    cursor: pointer;
}

.search-box {
    position: relative;
}

.search-box input {
    width: 300px;
    padding: 0.625rem 1rem 0.625rem 2.5rem;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    font-size: 0.9rem;
    transition: var(--transition);
    background: var(--gray-50);
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
    background: white;
}

.search-box i {
    position: absolute;
    left: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-400);
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-btn {
    width: 40px;
    height: 40px;
    border: none;
    background: var(--gray-100);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--gray-600);
    position: relative;
}

.header-btn:hover {
    background: var(--gray-200);
    color: var(--gray-800);
}

.header-btn .badge {
    position: absolute;
    top: -2px;
    right: -2px;
    width: 18px;
    height: 18px;
    background: var(--danger);
    color: white;
    font-size: 0.65rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Page Content */
.page-content {
    padding: 2rem;
}

.page-header {
    margin-bottom: 2rem;
}

.page-title {
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
}

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

/* Cards */
.card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

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

.card-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.card-title {
    font-size: 1.1rem;
    font-weight: 600;
}

.card-body {
    padding: 1.5rem;
}

.card-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--gray-100);
    background: var(--gray-50);
}

/* Stats Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    transition: var(--transition);
}

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

.stat-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.stat-icon.primary {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
}

.stat-icon.success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

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

.stat-icon.info {
    background: rgba(59, 130, 246, 0.1);
    color: var(--info);
}

.stat-content {
    flex: 1;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--gray-900);
}

.stat-label {
    color: var(--gray-500);
    font-size: 0.9rem;
}

.stat-change {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.8rem;
    margin-top: 0.5rem;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius);
}

.stat-change.positive {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.stat-change.negative {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--gray-100);
    color: var(--gray-700);
}

.btn-secondary:hover {
    background: var(--gray-200);
}

.btn-success {
    background: var(--success);
    color: white;
}

.btn-success:hover {
    opacity: 0.9;
}

.btn-danger {
    background: var(--danger);
    color: white;
}

.btn-danger:hover {
    opacity: 0.9;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--gray-300);
    color: var(--gray-700);
}

.btn-outline:hover {
    background: var(--gray-100);
    border-color: var(--gray-400);
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.8rem;
}

.btn-lg {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
}

.btn-icon {
    width: 36px;
    height: 36px;
    padding: 0;
    border-radius: var(--radius);
}

/* Forms */
.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--gray-700);
    font-size: 0.9rem;
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 0.95rem;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    transition: var(--transition);
    background: white;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

textarea.form-control {
    resize: vertical;
    min-height: 100px;
}

select.form-control {
    cursor: pointer;
}

.form-text {
    font-size: 0.8rem;
    color: var(--gray-500);
    margin-top: 0.375rem;
}

.form-error {
    color: var(--danger);
    font-size: 0.8rem;
    margin-top: 0.375rem;
}

/* Tables */
.table-container {
    overflow-x: auto;
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th,
.table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--gray-100);
}

.table th {
    font-weight: 600;
    color: var(--gray-600);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    background: var(--gray-50);
}

.table tbody tr {
    transition: var(--transition);
}

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

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.625rem;
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: var(--radius-2xl);
}

.badge-primary {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
}

.badge-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

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

.badge-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

.badge-info {
    background: rgba(59, 130, 246, 0.1);
    color: var(--info);
}

/* Vocabulary Cards */
.vocab-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

.vocab-card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

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

.vocab-card-header {
    padding: 1.25rem 1.5rem;
    background: var(--gradient-primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.vocab-word {
    font-size: 1.5rem;
    font-weight: 700;
}

.vocab-speak-btn {
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.2);
    border: none;
    border-radius: 50%;
    color: white;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.vocab-speak-btn:hover {
    background: rgba(255,255,255,0.3);
    transform: scale(1.1);
}

.vocab-card-body {
    padding: 1.5rem;
}

.vocab-meaning {
    font-size: 1rem;
    color: var(--gray-700);
    margin-bottom: 1rem;
}

.vocab-example {
    padding: 1rem;
    background: var(--gray-50);
    border-radius: var(--radius);
    border-left: 3px solid var(--primary);
    font-style: italic;
    color: var(--gray-600);
    font-size: 0.9rem;
}

.vocab-card-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.vocab-meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.vocab-topics {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.vocab-actions {
    display: flex;
    gap: 0.5rem;
}

/* Status Selector */
.status-selector {
    display: flex;
    gap: 0.5rem;
}

.status-btn {
    padding: 0.375rem 0.75rem;
    border: 1px solid var(--gray-200);
    background: white;
    border-radius: var(--radius);
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.status-btn:hover {
    border-color: var(--gray-300);
}

.status-btn.active.new {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--info);
    color: var(--info);
}

.status-btn.active.learning {
    background: rgba(245, 158, 11, 0.1);
    border-color: var(--warning);
    color: var(--warning);
}

.status-btn.active.mastered {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--success);
    color: var(--success);
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9) translateY(20px);
    transition: var(--transition);
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 600;
}

.modal-close {
    width: 32px;
    height: 32px;
    border: none;
    background: var(--gray-100);
    border-radius: var(--radius);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.modal-close:hover {
    background: var(--gray-200);
}

.modal-body {
    padding: 1.5rem;
}

.modal-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--gray-100);
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 3000;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.toast {
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 300px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast-icon {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.toast.success .toast-icon {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.toast.error .toast-icon {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

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

.toast-message {
    flex: 1;
    font-size: 0.9rem;
}

.toast-close {
    background: none;
    border: none;
    color: var(--gray-400);
    cursor: pointer;
}

/* Auth Pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 2rem;
}

.auth-card {
    background: white;
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 440px;
    padding: 2.5rem;
}

.auth-logo {
    text-align: center;
    margin-bottom: 2rem;
}

.auth-logo-icon {
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin: 0 auto 1rem;
}

.auth-logo h1 {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
}

.auth-logo p {
    color: var(--gray-500);
    font-size: 0.9rem;
}

.auth-form .form-group {
    margin-bottom: 1.5rem;
}

.auth-form .btn {
    width: 100%;
    padding: 0.875rem;
    font-size: 1rem;
}

.auth-divider {
    display: flex;
    align-items: center;
    margin: 1.5rem 0;
}

.auth-divider::before,
.auth-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--gray-200);
}

.auth-divider span {
    padding: 0 1rem;
    color: var(--gray-500);
    font-size: 0.85rem;
}

.auth-footer {
    text-align: center;
    margin-top: 1.5rem;
    color: var(--gray-500);
    font-size: 0.9rem;
}

.auth-footer a {
    font-weight: 500;
}

/* File Upload */
.file-upload {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
}

.file-upload:hover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.02);
}

.file-upload.drag-over {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
}

.file-upload-icon {
    font-size: 3rem;
    color: var(--gray-400);
    margin-bottom: 1rem;
}

.file-upload-text {
    color: var(--gray-600);
    margin-bottom: 0.5rem;
}

.file-upload-hint {
    font-size: 0.8rem;
    color: var(--gray-400);
}

.file-upload input {
    display: none;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 2rem;
}

.empty-state-icon {
    font-size: 4rem;
    color: var(--gray-300);
    margin-bottom: 1rem;
}

.empty-state h3 {
    color: var(--gray-600);
    margin-bottom: 0.5rem;
}

.empty-state p {
    color: var(--gray-500);
    margin-bottom: 1.5rem;
}

/* Loading */
.loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 3rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Topics List */
.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.topic-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 4px solid var(--primary);
}

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

.topic-name {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.topic-description {
    color: var(--gray-500);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.topic-stats {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--gray-100);
}

.topic-stat {
    display: flex;
    align-items: center;
    gap: 0.375rem;
    font-size: 0.85rem;
    color: var(--gray-500);
}

.topic-stat i {
    color: var(--primary);
}

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

    .sidebar.open {
        transform: translateX(0);
    }

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

    .menu-toggle {
        display: block;
    }
}

@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

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

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

    .search-box input {
        width: 200px;
    }

    .page-content {
        padding: 1rem;
    }

    .card-body {
        padding: 1rem;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 1rem;
    }

    .search-box {
        display: none;
    }

    .header-right .header-btn:not(:last-child) {
        display: none;
    }

    .auth-card {
        padding: 1.5rem;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-300);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

/* Utility Classes */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-primary { color: var(--primary); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-muted { color: var(--gray-500); }
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 1rem; }
.hidden { display: none !important; }

/* View Toggle */
.view-toggle {
    display: flex;
    background: var(--gray-100);
    border-radius: var(--radius);
    padding: 0.25rem;
    margin-right: 0.5rem;
}

.view-toggle-btn {
    width: 36px;
    height: 32px;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--gray-500);
}

.view-toggle-btn:hover {
    color: var(--gray-700);
}

.view-toggle-btn.active {
    background: white;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
}

/* Vocabulary List View */
.vocab-list {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.vocab-table-wrapper {
    overflow-x: auto;
}

.vocab-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 900px;
}

.vocab-table thead {
    background: var(--gray-50);
    position: sticky;
    top: 0;
    z-index: 10;
}

.vocab-table th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--gray-600);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-bottom: 2px solid var(--gray-200);
    white-space: nowrap;
}

.vocab-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--gray-100);
    vertical-align: middle;
}

.vocab-table tbody tr {
    transition: var(--transition);
}

.vocab-table tbody tr:hover {
    background: var(--gray-50);
}

.vocab-row-word {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.vocab-row-word strong {
    color: var(--gray-900);
    font-size: 1rem;
}

.vocab-row-phonetics {
    color: var(--gray-500);
    font-size: 0.85rem;
}

.vocab-row-meaning {
    color: var(--gray-700);
    font-size: 0.9rem;
    max-width: 300px;
    line-height: 1.4;
}

.vocab-row-example {
    color: var(--gray-500);
    font-size: 0.8rem;
    font-style: italic;
    margin-top: 0.25rem;
    max-width: 300px;
}

.vocab-row-vi {
    color: var(--gray-600);
    font-size: 0.9rem;
    max-width: 200px;
}

.form-control-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.8rem;
}

.status-select {
    border-color: var(--gray-200);
    cursor: pointer;
}

.status-select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.1);
}

/* Responsive List View */
@media (max-width: 1024px) {
    .vocab-table {
        min-width: 700px;
    }

    .vocab-row-meaning,
    .vocab-row-example,
    .vocab-row-vi {
        max-width: 200px;
    }
}

@media (max-width: 768px) {
    .view-toggle {
        display: none;
    }
}

/* Pagination Styles */
.pagination-container {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1.25rem 1.5rem;
    margin-top: 1.5rem;
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    flex-wrap: wrap;
    gap: 1.25rem;
}

.pagination-info {
    color: var(--gray-600);
    font-size: 0.875rem;
    font-weight: 500;
    background: var(--gray-100);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-lg);
}

.pagination {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.pagination-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 0.75rem;
    border: none;
    background: var(--gray-100);
    color: var(--gray-700);
    font-size: 0.9rem;
    font-weight: 600;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: var(--transition);
}

.pagination-btn:hover:not(.disabled):not(.active) {
    background: var(--gray-200);
    color: var(--gray-900);
    transform: translateY(-1px);
}

.pagination-btn.active {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.pagination-btn.disabled {
    opacity: 0.4;
    cursor: not-allowed;
    background: var(--gray-50);
}

.pagination-btn.nav-btn {
    background: white;
    border: 1px solid var(--gray-200);
    padding: 0 1rem;
    gap: 0.5rem;
    font-weight: 500;
}

.pagination-btn.nav-btn:hover:not(.disabled) {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.pagination-btn.nav-btn .btn-text {
    display: inline;
}

.pagination-ellipsis {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    color: var(--gray-400);
    font-size: 1rem;
    font-weight: 600;
}

@media (max-width: 768px) {
    .pagination-container {
        padding: 1rem;
        gap: 0.75rem;
    }

    .pagination {
        gap: 0.35rem;
    }

    .pagination-btn {
        min-width: 36px;
        height: 36px;
        font-size: 0.85rem;
        padding: 0 0.5rem;
    }

    .pagination-btn.nav-btn {
        padding: 0 0.75rem;
    }

    .pagination-btn.nav-btn .btn-text {
        display: none;
    }

    .pagination-info {
        font-size: 0.8rem;
        padding: 0.4rem 0.75rem;
    }
}

/* ===========================================
   LEARNING MODULE STYLES
   =========================================== */

/* Learning Plans Grid */
.plans-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.5rem;
}

.plan-card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
    cursor: pointer;
}

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

.plan-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--gray-100);
}

.plan-name {
    font-size: 1.125rem;
    font-weight: 600;
    margin: 0;
}

.plan-card-body {
    padding: 1.5rem;
}

.plan-info {
    display: grid;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
}

.plan-info-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.875rem;
    color: var(--gray-600);
}

.plan-info-item i {
    width: 16px;
    color: var(--gray-400);
}

.plan-progress {
    margin-bottom: 0.5rem;
}

.progress-bar {
    height: 8px;
    background: var(--gray-100);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 4px;
    transition: width 0.3s;
}

.progress-text {
    font-size: 0.875rem;
    color: var(--gray-500);
}

.plan-card-footer {
    display: flex;
    gap: 0.5rem;
    padding: 0 1.5rem 1.5rem;
}

/* Form Enhancements for Learning */
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.checkbox-group {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem;
    background: var(--gray-50);
    border-radius: var(--radius);
    cursor: pointer;
    transition: background 0.2s;
}

.checkbox-label:hover {
    background: var(--gray-100);
}

.checkbox-label input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
}

.topic-count {
    font-size: 0.75rem;
    color: var(--gray-400);
    margin-left: auto;
}

.preview-box {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 1rem;
    margin-top: 1rem;
}

.preview-title {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--gray-500);
    margin-bottom: 0.5rem;
}

.preview-content {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--primary);
}

/* Plan Details */
.plan-details {
    padding: 0.5rem;
}

.detail-section {
    margin-bottom: 1.5rem;
}

.detail-section h4 {
    font-size: 0.875rem;
    text-transform: uppercase;
    color: var(--gray-500);
    margin-bottom: 0.75rem;
}

.detail-grid {
    display: grid;
    gap: 0.75rem;
}

.detail-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.detail-label {
    color: var(--gray-500);
}

.topic-badges,
.level-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.progress-stats {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1rem;
    text-align: center;
}

.progress-stat {
    padding: 1rem;
    background: var(--gray-50);
    border-radius: var(--radius);
}

.stat-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--gray-500);
}

.detail-actions {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

/* Modal Large */
.modal.modal-lg {
    max-width: 600px;
}

/* Utility Classes */
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-muted { color: var(--gray-500); }
.text-primary { color: var(--primary); }
.text-center { text-align: center; }
.mt-4 { margin-top: 1.5rem; }

.hidden {
    display: none !important;
}

/* Header Title */
.header-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin: 0;
}

/* Speak Button in Cards */
.speak-btn {
    background: var(--primary);
    color: white;
    border: none;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.speak-btn:hover {
    background: var(--primary-dark);
    transform: scale(1.1);
}

@media (max-width: 768px) {
    .plans-grid {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .checkbox-group {
        grid-template-columns: 1fr;
    }

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