/* CSS Variables */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --success-color: #10b981;
    --success-dark: #059669;
    --danger-color: #ef4444;
    --danger-dark: #dc2626;
    --warning-color: #f59e0b;
    --warning-dark: #d97706;
    --info-color: #06b6d4;
    
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    --border-color: #e2e8f0;
    --border-radius: 0.5rem;
    --border-radius-lg: 0.75rem;
    
    --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);
    
    --sidebar-width: 260px;
    --header-height: 60px;
    
    --transition: all 0.2s ease;
}

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

html {
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    z-index: 1000;
    transition: transform 0.3s ease;
}

.sidebar-header {
    padding: 1.25rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-header h1 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-menu {
    flex: 1;
    list-style: none;
    padding: 0.75rem;
    overflow-y: auto;
}

.nav-item {
    margin-bottom: 0.25rem;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    font-weight: 500;
}

.nav-link:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.nav-link.active {
    background-color: var(--primary-color);
    color: white;
}

.nav-link i {
    width: 20px;
    text-align: center;
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

/* Main Content */
.main-content {
    margin-left: var(--sidebar-width);
    padding: 1.5rem;
    min-height: 100vh;
}

/* Mobile Navigation Toggle */
.nav-toggle {
    display: none;
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1001;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    width: 44px;
    height: 44px;
    cursor: pointer;
    font-size: 1.25rem;
    box-shadow: var(--shadow-md);
}

.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 999;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1;
    text-decoration: none;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.btn-block {
    width: 100%;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
}

.btn-secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background-color: var(--border-color);
}

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

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

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

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

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

.btn-warning:hover {
    background-color: var(--warning-dark);
}

.btn-outline {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.btn-outline:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-sm {
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
}

.btn-lg {
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
}

/* Cards */
.card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
}

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

.card-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.card-body {
    padding: 1.25rem;
}

.card-footer {
    padding: 1rem 1.25rem;
    border-top: 1px solid var(--border-color);
    background-color: var(--bg-tertiary);
    border-radius: 0 0 var(--border-radius-lg) var(--border-radius-lg);
}

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

.form-label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.form-hint {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

.form-control {
    width: 100%;
    padding: 0.625rem 0.875rem;
    font-size: 1rem;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    transition: var(--transition);
    -webkit-appearance: none;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-control::placeholder {
    color: var(--text-muted);
}

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

select.form-control {
    cursor: pointer;
}

/* Checkbox and Radio */
.form-check {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 0.5rem;
}

.form-check:hover {
    background-color: var(--bg-tertiary);
    border-color: var(--primary-light);
}

.form-check.selected {
    background-color: rgba(37, 99, 235, 0.05);
    border-color: var(--primary-color);
}

.form-check input[type="radio"],
.form-check input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin-top: 0.125rem;
    flex-shrink: 0;
    accent-color: var(--primary-color);
}

.form-check-label {
    flex: 1;
    cursor: pointer;
}

/* Input Groups */
.input-group {
    display: flex;
    gap: 0.5rem;
}

.input-group .form-control {
    flex: 1;
}

/* Alerts */
.flash-messages {
    margin-bottom: 1.5rem;
}

.alert {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.25rem;
    border-radius: var(--border-radius);
    margin-bottom: 0.75rem;
    font-weight: 500;
}

.alert-success {
    background-color: #ecfdf5;
    color: var(--success-dark);
    border: 1px solid #a7f3d0;
}

.alert-error {
    background-color: #fef2f2;
    color: var(--danger-dark);
    border: 1px solid #fecaca;
}

.alert-warning {
    background-color: #fffbeb;
    color: var(--warning-dark);
    border: 1px solid #fde68a;
}

.alert-info {
    background-color: #ecfeff;
    color: #0891b2;
    border: 1px solid #a5f3fc;
}

.alert-close {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    padding: 0.25rem;
    opacity: 0.7;
}

.alert-close:hover {
    opacity: 1;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 1.25rem;
    text-align: center;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1.2;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

.stat-card.success .stat-value {
    color: var(--success-color);
}

.stat-card.danger .stat-value {
    color: var(--danger-color);
}

.stat-card.warning .stat-value {
    color: var(--warning-color);
}

/* Progress Bar */
.progress {
    height: 0.5rem;
    background-color: var(--bg-tertiary);
    border-radius: 9999px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--primary-color);
    border-radius: 9999px;
    transition: width 0.3s ease;
}

.progress-bar.success {
    background-color: var(--success-color);
}

.progress-bar.danger {
    background-color: var(--danger-color);
}

/* Tables */
.table-responsive {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

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

.table th,
.table td {
    padding: 0.875rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    font-weight: 600;
    color: var(--text-secondary);
    background-color: var(--bg-tertiary);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.025em;
}

.table tbody tr:hover {
    background-color: var(--bg-tertiary);
}

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.625rem;
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: 9999px;
    text-transform: uppercase;
    letter-spacing: 0.025em;
}

.badge-primary {
    background-color: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
}

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

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

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

.badge-info {
    background-color: rgba(6, 182, 212, 0.1);
    color: var(--info-color);
}

/* Page Header */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.page-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.page-subtitle {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

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

/* Breadcrumb */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

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

.breadcrumb a:hover {
    text-decoration: underline;
}

.breadcrumb-separator {
    color: var(--text-muted);
}

/* Question Cards */
.question-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.question-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 1.25rem;
    transition: var(--transition);
}

.question-card:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow);
}

.question-meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    flex-wrap: wrap;
}

.question-text {
    color: var(--text-primary);
    font-weight: 500;
    line-height: 1.5;
    margin-bottom: 1rem;
}

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

/* Answer Options */
.answer-options {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.answer-option {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

.answer-option:hover {
    border-color: var(--primary-light);
    background-color: var(--bg-tertiary);
}

.answer-option.selected {
    border-color: var(--primary-color);
    background-color: rgba(37, 99, 235, 0.05);
}

.answer-option.correct {
    border-color: var(--success-color);
    background-color: rgba(16, 185, 129, 0.1);
}

.answer-option.incorrect {
    border-color: var(--danger-color);
    background-color: rgba(239, 68, 68, 0.1);
}

.answer-option input[type="radio"] {
    width: 20px;
    height: 20px;
    margin-top: 0.125rem;
    flex-shrink: 0;
    accent-color: var(--primary-color);
}

.answer-text {
    flex: 1;
}

.answer-indicator {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    flex-shrink: 0;
}

.answer-indicator.correct {
    background-color: var(--success-color);
    color: white;
}

.answer-indicator.incorrect {
    background-color: var(--danger-color);
    color: white;
}

/* Result Display */
.result-display {
    text-align: center;
    padding: 2rem;
    margin-bottom: 1.5rem;
}

.result-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.result-icon.correct {
    color: var(--success-color);
}

.result-icon.incorrect {
    color: var(--danger-color);
}

.result-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.result-title.correct {
    color: var(--success-color);
}

.result-title.incorrect {
    color: var(--danger-color);
}

/* Explanation Box */
.explanation-box {
    background-color: var(--bg-tertiary);
    border-left: 4px solid var(--info-color);
    padding: 1rem 1.25rem;
    margin: 1.5rem 0;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

.explanation-title {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.explanation-text {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Filter Section */
.filter-section {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 1rem;
    margin-bottom: 1.5rem;
}

.filter-row {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    align-items: flex-end;
}

.filter-group {
    flex: 1;
    min-width: 150px;
}

.filter-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.375rem;
    color: var(--text-secondary);
}

/* Tab Navigation */
.tabs {
    display: flex;
    gap: 0.25rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.tab {
    padding: 0.75rem 1.25rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
    transition: var(--transition);
}

.tab:hover {
    color: var(--text-primary);
}

.tab.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab .count {
    margin-left: 0.5rem;
    background-color: var(--bg-tertiary);
    padding: 0.125rem 0.5rem;
    border-radius: 9999px;
    font-size: 0.75rem;
}

/* Grid Layouts */
.grid {
    display: grid;
    gap: 1.5rem;
}

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

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

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

/* Practice Progress */
.practice-progress {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 1rem 1.25rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}

.practice-progress-info {
    display: flex;
    gap: 1.5rem;
}

.practice-progress-item {
    text-align: center;
}

.practice-progress-value {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.practice-progress-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1.5rem;
    color: var(--text-muted);
}

.empty-state-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

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

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

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

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

.mb-0 {
    margin-bottom: 0;
}

.mb-1 {
    margin-bottom: 0.5rem;
}

.mb-2 {
    margin-bottom: 1rem;
}

.mb-3 {
    margin-bottom: 1.5rem;
}

.mt-1 {
    margin-top: 0.5rem;
}

.mt-2 {
    margin-top: 1rem;
}

.mt-3 {
    margin-top: 1.5rem;
}

.d-flex {
    display: flex;
}

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

.justify-content-between {
    justify-content: space-between;
}

.gap-1 {
    gap: 0.5rem;
}

.gap-2 {
    gap: 1rem;
}

.flex-wrap {
    flex-wrap: wrap;
}

/* Answer Input Styles */
.answer-input-group {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.answer-input-group .form-control {
    flex: 1;
    min-width: 150px;
}

/* Equation Input */
.equation-input {
    font-family: 'Courier New', monospace;
    font-size: 1.125rem;
}

.equation-hint {
    background-color: var(--bg-tertiary);
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius);
    margin-top: 0.75rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Dynamic Answer Builder */
.answer-builder {
    margin-bottom: 1.5rem;
}

.answer-builder-item {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    align-items: flex-start;
}

.answer-builder-item input[type="radio"] {
    margin-top: 0.75rem;
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

.answer-builder-fields {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.answer-builder-item .remove-answer {
    margin-top: 0.5rem;
}

.add-answer-btn {
    margin-top: 0.5rem;
}

/* Chart Container */
.chart-container {
    position: relative;
    height: 300px;
    width: 100%;
}

/* Mobile Responsive */
@media (max-width: 1024px) {
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.active {
        transform: translateX(0);
    }
    
    .nav-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    .overlay.active {
        display: block;
    }
    
    .main-content {
        margin-left: 0;
        padding: 1rem;
        padding-top: 4.5rem;
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .page-actions {
        width: 100%;
    }
    
    .page-actions .btn {
        flex: 1;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .filter-row {
        flex-direction: column;
    }
    
    .filter-group {
        width: 100%;
    }
    
    .practice-progress {
        flex-direction: column;
        text-align: center;
    }
    
    .btn-lg {
        width: 100%;
    }
    
    .table th,
    .table td {
        padding: 0.625rem 0.75rem;
        font-size: 0.875rem;
    }
    
    .answer-builder-item {
        flex-wrap: wrap;
    }
    
    .answer-input-group {
        flex-direction: column;
    }
    
    .answer-input-group .form-control {
        width: 100%;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .stat-value {
        font-size: 1.5rem;
    }
    
    .tabs {
        gap: 0;
    }
    
    .tab {
        padding: 0.625rem 0.875rem;
        font-size: 0.875rem;
    }
    
    .card-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .card-header .btn {
        width: 100%;
    }
}

/* ===========================================
   Authentication Styles
   =========================================== */

.auth-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: calc(100vh - 100px);
    padding: 2rem;
}

.auth-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 420px;
    padding: 2rem;
}

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

.auth-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.auth-subtitle {
    color: var(--text-muted);
}

.auth-form .form-group {
    margin-bottom: 1.25rem;
}

.auth-footer {
    text-align: center;
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.auth-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.auth-footer a:hover {
    text-decoration: underline;
}

/* Checkbox styling */
.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.checkbox-label input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    cursor: pointer;
}

/* Sidebar User */
.sidebar-user {
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: #fff;
    text-decoration: none;
    padding: 0.5rem;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.user-info:hover {
    background: rgba(255, 255, 255, 0.1);
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
}

.user-details {
    flex: 1;
    min-width: 0;
}

.user-name {
    font-weight: 500;
    font-size: 0.875rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.user-email {
    font-size: 0.75rem;
    opacity: 0.7;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Profile Details */
.detail-grid {
    display: grid;
    gap: 1rem;
}

.detail-item {
    padding: 1rem;
    background: var(--bg-tertiary);
    border-radius: var(--border-radius);
}

.detail-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 0.25rem;
}

.detail-value {
    font-size: 1rem;
    color: var(--text-primary);
}

@media (min-width: 768px) {
    .detail-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ==================== Summernote WYSIWYG Editor Styles ==================== */
textarea.richtext-editor {
    min-height: 200px;
    resize: vertical;
    display: block;
    width: 100%;
}

/* Summernote editor container */
.note-editor {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 1rem;
}

.note-editor.note-frame {
    border-color: var(--border-color);
}

/* Summernote toolbar */
.note-toolbar {
    background-color: var(--surface);
    border-bottom: 1px solid var(--border-color);
    padding: 0.5rem;
}

/* Summernote editing area */
.note-editable {
    background-color: var(--background);
    color: var(--text-primary);
    padding: 1rem;
    min-height: 200px;
}

/* Summernote placeholder */
.note-placeholder {
    color: var(--text-muted);
}

/* Summernote buttons */
.note-btn {
    background-color: var(--surface);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.note-btn:hover {
    background-color: var(--hover-bg);
}

/* Summernote dropdown */
.note-dropdown-menu {
    background-color: var(--surface);
    border: 1px solid var(--border-color);
}

.note-dropdown-item {
    color: var(--text-primary);
}

.note-dropdown-item:hover {
    background-color: var(--hover-bg);
}

/* Summernote modal */
.note-modal .modal-content {
    background-color: var(--surface);
    color: var(--text-primary);
}

/* Summernote statusbar */
.note-statusbar {
    background-color: var(--surface);
    border-top: 1px solid var(--border-color);
}

/* Fix table borders in editor */
.note-editable table {
    border-collapse: collapse;
    width: 100%;
    margin: 1rem 0;
}

.note-editable table td,
.note-editable table th {
    border: 1px solid var(--border-color);
    padding: 0.5rem;
}

.note-editable table th {
    background-color: var(--surface);
    font-weight: 600;
}

/* ==================== Tags Styles ==================== */
.tags-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.tag-card {
    background: var(--surface);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.tag-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.tag-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.tag-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
}

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

.tag-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    padding: 1rem 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.tag-stats .stat-item {
    text-align: center;
}

.tag-stats .stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.tag-stats .stat-label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

.tag-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 1rem;
}

.color-picker-group {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.form-control-color {
    width: 60px;
    height: 50px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
}

.tag-preview {
    padding: 1.5rem;
    background: var(--background);
    border: 1px dashed var(--border-color);
    border-radius: 8px;
    text-align: center;
}

.tag-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 0.5rem 0;
}

.tag-item {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 0.8rem;
    border-radius: 4px;
    font-size: 0.85rem;
    color: white;
    font-weight: 500;
}

.tag-select-container {
    max-height: 200px;
    overflow-y: auto;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.75rem;
}

.tag-checkbox-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
}

.tag-checkbox-item:hover {
    background-color: var(--hover-bg);
}

.tag-checkbox-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.tag-checkbox-label {
    flex: 1;
    cursor: pointer;
}