/**
 * ExamReady Stylesheet
 * Clean, neutral tech aesthetic with light/dark mode support
 */

/* ===== CSS VARIABLES ===== */
:root {
    /* Light Mode Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --text-muted: #adb5bd;
    --border-color: #dee2e6;
    --accent-primary: #0d6efd;
    --accent-secondary: #6610f2;
    --success: #198754;
    --warning: #ffc107;
    --danger: #dc3545;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    
    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.25s ease;
    --transition-slow: 0.35s ease;
}

/* Dark Mode Colors */
[data-theme="dark"] {
    --bg-primary: #1a1d23;
    --bg-secondary: #22252b;
    --bg-tertiary: #2c3038;
    --text-primary: #e9ecef;
    --text-secondary: #adb5bd;
    --text-muted: #6c757d;
    --border-color: #3a3f47;
    --accent-primary: #4c9aff;
    --accent-secondary: #8b5cf6;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
}

/* ===== GLOBAL STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-base), color var(--transition-base);
}

/* ===== HEADER ===== */
.site-header {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all var(--transition-base);
    backdrop-filter: blur(8px);
    background-color: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] .site-header {
    background-color: rgba(26, 29, 35, 0.95);
}

.navbar {
    padding: var(--spacing-sm) 0;
}

.navbar-brand {
    display: flex;
    flex-direction: column;
    text-decoration: none;
    transition: transform var(--transition-fast);
}

.navbar-brand:hover {
    transform: translateY(-2px);
}

.brand-name {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.brand-subtitle {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-top: -4px;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    color: var(--accent-primary);
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 1rem;
    right: 1rem;
    height: 2px;
    background-color: var(--accent-primary);
    border-radius: 2px;
}

/* Theme Toggle Button */
.btn-theme-toggle {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--text-primary);
    margin-left: 0.5rem;
}

.btn-theme-toggle:hover {
    background: var(--bg-tertiary);
    transform: scale(1.05);
}

.btn-theme-toggle i {
    font-size: 1.2rem;
}

/* ===== MAIN CONTENT ===== */
.main-content {
    min-height: calc(100vh - 200px);
    padding: var(--spacing-xl) 0;
}

.page-header {
    margin-bottom: var(--spacing-xl);
    text-align: center;
}

.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.page-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.lead {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
}

/* ===== HOME PAGE ===== */
.hero-section {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.how-it-works {
    margin-bottom: var(--spacing-xl);
}

.how-it-works h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.feature-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    text-align: center;
    transition: all var(--transition-base);
    height: 100%;
}

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

.feature-card i {
    font-size: 2.5rem;
    color: var(--accent-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.feature-card p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin: 0;
}

/* Quick Links */
.quick-links {
    margin-bottom: var(--spacing-xl);
}

.quick-links h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.quick-link-card {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

.quick-link-card:hover {
    background: var(--bg-tertiary);
    transform: translateX(4px);
    box-shadow: var(--shadow-sm);
}

.quick-link-card i:first-child {
    font-size: 1.5rem;
    color: var(--accent-primary);
}

.quick-link-card span {
    flex: 1;
    font-weight: 500;
}

.quick-link-card i:last-child {
    color: var(--text-muted);
    transition: transform var(--transition-fast);
}

.quick-link-card:hover i:last-child {
    transform: translateX(4px);
}

/* Latest Updates */
.latest-updates h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.updates-list {
    max-width: 800px;
    margin: 0 auto;
}

.update-item {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    display: flex;
    gap: var(--spacing-md);
    align-items: start;
    transition: all var(--transition-base);
}

.update-item:hover {
    box-shadow: var(--shadow-sm);
}

.update-icon {
    width: 40px;
    height: 40px;
    background: var(--accent-primary);
    color: white;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.update-content {
    flex: 1;
}

.update-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.update-meta {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.update-date {
    font-size: 0.875rem;
    color: var(--text-muted);
    white-space: nowrap;
}

/* ===== FILTERS & SEARCH ===== */
.filters-section {
    margin-bottom: var(--spacing-lg);
}

.search-box {
    position: relative;
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.search-box .form-control {
    padding-left: 2.75rem;
}

.form-control,
.form-select {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    border-radius: 8px;
    padding: 0.625rem 1rem;
    transition: all var(--transition-fast);
}

.form-control:focus,
.form-select:focus {
    background-color: var(--bg-primary);
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.1);
    outline: none;
}

[data-theme="dark"] .form-control:focus,
[data-theme="dark"] .form-select:focus {
    box-shadow: 0 0 0 3px rgba(76, 154, 255, 0.2);
}

.results-info {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

/* ===== GUIDES GRID ===== */
.guides-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.guide-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
    transition: all var(--transition-base);
    display: flex;
    flex-direction: column;
}

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

.guide-header {
    margin-bottom: var(--spacing-sm);
}

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

.guide-meta {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-sm);
}

.guide-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.625rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-secondary);
    font-weight: 500;
}

.guide-date {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: auto;
    padding-top: var(--spacing-sm);
}

.guide-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: var(--spacing-sm);
}

.btn-guide {
    flex: 1;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: center;
    text-decoration: none;
    display: inline-block;
}

.btn-guide:hover {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
}

.btn-guide.btn-preview {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
}

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

/* Desktop-only preview button */
@media (max-width: 991.98px) {
    .btn-guide.btn-preview {
        display: none;
    }
}

/* ===== TASKS PAGE ===== */
.task-tabs-section {
    margin-bottom: var(--spacing-lg);
}

.task-tabs {
    border-bottom: 2px solid var(--border-color);
    margin-bottom: var(--spacing-lg);
}

.task-tabs .nav-link {
    border: none;
    color: var(--text-secondary);
    font-weight: 600;
    padding: var(--spacing-sm) var(--spacing-md);
    margin-right: 0.5rem;
    border-radius: 8px 8px 0 0;
    transition: all var(--transition-fast);
}

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

.task-tabs .nav-link.active {
    background: var(--bg-secondary);
    color: var(--accent-primary);
    border-bottom: 2px solid var(--accent-primary);
}

.task-tab-content {
    padding-top: var(--spacing-md);
}

.task-controls {
    margin-bottom: var(--spacing-lg);
}

/* ===== PAST QUESTIONS ===== */
.past-papers-section {
    margin-bottom: var(--spacing-xl);
}

.accordion-item {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    margin-bottom: var(--spacing-sm);
    overflow: hidden;
}

.accordion-button {
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-weight: 600;
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-fast);
}

.accordion-button:not(.collapsed) {
    background: var(--bg-tertiary);
    color: var(--accent-primary);
    box-shadow: none;
}

.accordion-button:focus {
    box-shadow: none;
    border-color: var(--border-color);
}

.accordion-button::after {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%236c757d'%3e%3cpath fill-rule='evenodd' d='M1.646 4.646a.5.5 0 0 1 .708 0L8 10.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z'/%3e%3c/svg%3e");
}

[data-theme="dark"] .accordion-button::after {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%23adb5bd'%3e%3cpath fill-rule='evenodd' d='M1.646 4.646a.5.5 0 0 1 .708 0L8 10.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z'/%3e%3c/svg%3e");
}

.accordion-body {
    padding: var(--spacing-lg);
    background: var(--bg-primary);
}

.paper-group {
    margin-bottom: var(--spacing-lg);
}

.paper-group:last-child {
    margin-bottom: 0;
}

.paper-group-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.paper-list {
    display: grid;
    gap: 0.75rem;
}

.paper-item {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-fast);
}

.paper-item:hover {
    box-shadow: var(--shadow-sm);
}

.paper-icon {
    width: 36px;
    height: 36px;
    background: var(--accent-primary);
    color: white;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.paper-info {
    flex: 1;
}

.paper-name {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.125rem;
}

.paper-type {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

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

.btn-paper {
    padding: 0.375rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.8125rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
}

.btn-paper:hover {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
}

/* ===== FAQ PAGE ===== */
.faq-actions {
    margin-bottom: var(--spacing-xl);
}

.action-card {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

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

.action-card i:first-child {
    font-size: 2rem;
    color: var(--accent-primary);
}

.action-card > div {
    flex: 1;
}

.action-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.action-card p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    margin: 0;
}

.action-card i:last-child {
    color: var(--text-muted);
}

.faq-section {
    max-width: 900px;
    margin: 0 auto;
}

.faq-category {
    margin-bottom: var(--spacing-lg);
}

.faq-category-header {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md) var(--spacing-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.faq-category-header:hover {
    background: var(--bg-tertiary);
}

.faq-category-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin: 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.faq-category-icon {
    font-size: 1.5rem;
    color: var(--accent-primary);
}

.faq-category-count {
    font-size: 0.875rem;
    color: var(--text-muted);
    background: var(--bg-tertiary);
    padding: 0.25rem 0.625rem;
    border-radius: 12px;
}

.faq-category-toggle {
    font-size: 1.25rem;
    color: var(--text-muted);
    transition: transform var(--transition-fast);
}

.faq-category.active .faq-category-toggle {
    transform: rotate(180deg);
}

.faq-items {
    display: none;
    padding: var(--spacing-md) 0;
}

.faq-category.active .faq-items {
    display: block;
}

.faq-item {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.faq-question-header {
    display: flex;
    align-items: start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.faq-question-id {
    background: var(--accent-primary);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    white-space: nowrap;
}

.faq-question-text {
    flex: 1;
    font-weight: 500;
    color: var(--text-primary);
}

.faq-error {
    background: var(--bg-tertiary);
    border-left: 3px solid var(--danger);
    padding: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    border-radius: 6px;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.faq-code {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    overflow-x: auto;
}

.faq-answers {
    margin-top: var(--spacing-sm);
}

.faq-answer {
    background: var(--bg-tertiary);
    border-left: 3px solid var(--accent-primary);
    padding: var(--spacing-sm);
    margin-bottom: 0.5rem;
    border-radius: 6px;
}

.faq-answer:last-child {
    margin-bottom: 0;
}

.faq-answer-text {
    font-size: 0.9375rem;
    color: var(--text-primary);
    margin: 0;
}

/* ===== HELP SECTION ===== */
.help-section {
    margin-top: var(--spacing-xl);
}

.info-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    display: flex;
    gap: var(--spacing-md);
}

.info-card i {
    font-size: 2rem;
    color: var(--accent-primary);
    flex-shrink: 0;
}

.info-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.info-card ul {
    margin: 0;
    padding-left: 1.25rem;
    color: var(--text-secondary);
}

.info-card li {
    margin-bottom: 0.5rem;
}

/* ===== LOADING & EMPTY STATES ===== */
.loading-state {
    text-align: center;
    padding: var(--spacing-xl);
}

.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
}

.empty-state i {
    font-size: 3rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
}

.empty-state h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* ===== MODAL ===== */
.modal-content {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
}

.modal-header {
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) var(--spacing-lg);
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.btn-close {
    filter: var(--bs-btn-close-white-filter);
    opacity: 0.5;
}

[data-theme="dark"] .btn-close {
    filter: invert(1);
}

.modal-body {
    padding: var(--spacing-lg);
}

/* ===== FOOTER ===== */
.site-footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-xl);
}

.footer-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 0.5rem;
}

.footer-meta {
    font-size: 0.8125rem;
    color: var(--text-muted);
    text-align: center;
    margin: 0;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 991.98px) {
    .page-title {
        font-size: 2rem;
    }
    
    .guides-grid {
        grid-template-columns: 1fr;
    }
    
    .task-tabs .nav-link {
        font-size: 0.9375rem;
        padding: 0.625rem 0.875rem;
    }
}

@media (max-width: 767.98px) {
    .main-content {
        padding: var(--spacing-lg) 0;
    }
    
    .page-title {
        font-size: 1.75rem;
    }
    
    .feature-card {
        padding: var(--spacing-md);
    }
    
    .quick-link-card {
        padding: var(--spacing-sm) var(--spacing-md);
    }
}

/* ===== UTILITIES ===== */
.text-truncate-2 {
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.3s ease;
}