/* ========================================
   帮助中心 - 全局样式
   模仿飞牛 fnOS 帮助中心风格
   ======================================== */

/* CSS 变量 */
:root {
    --primary: #4f46e5;
    --primary-light: #818cf8;
    --primary-dark: #3730a3;
    --primary-bg: #eef2ff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --bg-body: #f8fafc;
    --bg-white: #ffffff;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.04);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;
    --transition: all 0.2s ease;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --max-width: 1200px;
    --max-width-doc: 1350px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: 15px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-body);
}

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

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

img {
    max-width: 100%;
    height: auto;
}

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ========================================
   Header
   ======================================== */
.header {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-inner {
    display: flex;
    align-items: center;
    height: 64px;
    gap: 24px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    white-space: nowrap;
    text-decoration: none;
}

.logo i {
    color: var(--primary);
    font-size: 24px;
}

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

.header-search {
    position: relative;
    flex: 1;
    max-width: 480px;
}

.header-search i.fa-search {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-size: 14px;
    z-index: 1;
}

.header-search input {
    width: 100%;
    padding: 9px 16px 9px 40px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    font-size: 14px;
    font-family: var(--font-family);
    background: var(--bg-body);
    color: var(--text-primary);
    transition: var(--transition);
    outline: none;
}

.header-search input:focus {
    background: var(--bg-white);
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.header-nav {
    display: flex;
    align-items: center;
    gap: 4px;
}

.header-nav a {
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    white-space: nowrap;
}

.header-nav a:hover,
.header-nav a.active {
    color: var(--primary);
    background: var(--primary-bg);
}

/* 头部用户登录 */
/* ========================================
   Hero Section (首页)
   ======================================== */
.hero {
    background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
    padding: 72px 0 64px;
    text-align: center;
    color: white;
}

.hero-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 28px;
    letter-spacing: -0.02em;
}

.hero-search {
    position: relative;
    max-width: 640px;
    margin: 0 auto;
    display: flex;
    align-items: center;
}

.hero-search-icon {
    position: absolute;
    left: 20px;
    font-size: 18px;
    color: var(--text-muted);
    z-index: 1;
}

.hero-search-input {
    width: 100%;
    padding: 16px 120px 16px 52px;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 16px;
    font-family: var(--font-family);
    color: var(--text-primary);
    background: var(--bg-white);
    box-shadow: var(--shadow-xl);
    outline: none;
    transition: var(--transition);
}

.hero-search-input:focus {
    box-shadow: var(--shadow-xl), 0 0 0 3px rgba(255,255,255,0.3);
}

.hero-search-input::placeholder {
    color: var(--text-muted);
}

.hero-search-btn {
    position: absolute;
    right: 6px;
    padding: 10px 24px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 15px;
    font-weight: 600;
    font-family: var(--font-family);
    cursor: pointer;
    transition: var(--transition);
}

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

/* ========================================
   Search Suggestions
   ======================================== */
.search-suggestions {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin-top: 6px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-color);
    display: none;
    z-index: 200;
    overflow: hidden;
}

.search-suggestions.active {
    display: block;
}

.search-suggestion-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 18px;
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
}

.search-suggestion-item:hover {
    background: var(--primary-bg);
}

.search-suggestion-item .suggestion-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.search-suggestion-item .suggestion-summary {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 2px;
}

.search-suggestion-item .suggestion-category {
    font-size: 11px;
    color: var(--primary);
    background: var(--primary-bg);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    white-space: nowrap;
    margin-top: 2px;
}

/* ========================================
   Categories Grid (首页)
   ======================================== */
.categories-section {
    padding: 48px 0 72px;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.category-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: var(--transition);
}

.category-card:hover {
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
    transform: translateY(-2px);
}

.category-card-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 14px;
}

.category-icon {
    width: 48px;
    height: 48px;
    background: var(--primary-bg);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.category-icon i {
    font-size: 22px;
    color: var(--primary);
}

.category-icon.large {
    width: 56px;
    height: 56px;
}

.category-icon.large i {
    font-size: 26px;
}

.category-name {
    font-size: 18px;
    font-weight: 600;
}

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

.category-name a:hover {
    color: var(--primary);
}

.category-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 16px;
}

.category-docs {
    list-style: none;
    margin-bottom: 16px;
}

.category-docs li {
    margin-bottom: 8px;
}

.category-docs li a {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--text-secondary);
    padding: 6px 0;
}

.category-docs li a i {
    font-size: 12px;
    color: var(--text-muted);
}

.category-docs li a:hover {
    color: var(--primary);
}

.category-more {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    font-weight: 500;
    color: var(--primary);
}

.category-more:hover {
    gap: 10px;
}

/* ========================================
   Page Section (分类页、详情页、搜索页)
   ======================================== */
.page-section {
    padding: 32px 0 72px;
}

.main {
    min-height: calc(100vh - 64px - 200px);
}

/* Breadcrumb */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 28px;
    font-size: 14px;
    flex-wrap: wrap;
}

.breadcrumb a {
    color: var(--text-secondary);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

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

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

.breadcrumb-current {
    color: var(--text-primary);
    font-weight: 500;
}

/* Category Header */
.category-header {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 32px;
}

.category-title {
    font-size: 28px;
    font-weight: 700;
}

.category-description {
    font-size: 15px;
    color: var(--text-secondary);
    margin-top: 6px;
}

/* Sub Categories */
.sub-categories {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 14px;
    margin-bottom: 32px;
}

.sub-category-card {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 18px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    transition: var(--transition);
}

.sub-category-card i {
    color: var(--primary);
    font-size: 16px;
}

.sub-category-card:hover {
    border-color: var(--primary-light);
    background: var(--primary-bg);
}

.sub-category-count {
    font-size: 12px;
    color: var(--text-muted);
    margin-left: auto;
}

/* Doc List */
.doc-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.doc-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 24px;
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
    border-bottom: 1px solid var(--border-light);
}

.doc-item:last-child {
    border-bottom: none;
}

.doc-item:hover {
    background: var(--primary-bg);
}

.doc-item-left {
    display: flex;
    align-items: center;
    gap: 16px;
    flex: 1;
    min-width: 0;
}

.doc-item-icon {
    font-size: 18px;
    color: var(--primary);
    flex-shrink: 0;
}

.doc-item-content {
    flex: 1;
    min-width: 0;
}

.doc-item-title {
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 2px;
}

.doc-item-summary {
    font-size: 13px;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.doc-item-arrow {
    color: var(--text-muted);
    font-size: 12px;
    flex-shrink: 0;
    margin-left: 16px;
    transition: var(--transition);
}

.doc-item:hover .doc-item-arrow {
    color: var(--primary);
    transform: translateX(3px);
}

/* ========================================
   Doc Detail Page
   ======================================== */
.doc-layout {
    display: grid;
    grid-template-columns: 200px 1fr 280px;
    gap: 32px;
    align-items: start;
}

.page-section:has(.doc-layout) > .container {
    max-width: var(--max-width-doc);
}

.doc-content {
    min-width: 0;
}

.doc-header {
    margin-bottom: 28px;
}

.doc-title {
    font-size: 30px;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 14px;
    letter-spacing: -0.02em;
}

.doc-meta {
    display: flex;
    align-items: center;
    gap: 18px;
    font-size: 13px;
    color: var(--text-muted);
}

.doc-meta i {
    margin-right: 4px;
}

.doc-summary {
    background: var(--primary-bg);
    border: 1px solid rgba(79, 70, 229, 0.15);
    border-radius: var(--radius-md);
    padding: 14px 18px;
    margin-bottom: 28px;
    font-size: 14px;
    color: var(--primary-dark);
    line-height: 1.6;
}

.doc-summary i {
    margin-right: 6px;
    color: var(--primary);
}

/* Doc Body Content Styles */
.doc-body {
    font-size: 15px;
    line-height: 1.8;
    color: var(--text-primary);
}

.doc-body h1 {
    font-size: 26px;
    font-weight: 700;
    margin: 36px 0 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
}

.doc-body h2 {
    font-size: 22px;
    font-weight: 600;
    margin: 30px 0 14px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-light);
}

.doc-body h3 {
    font-size: 18px;
    font-weight: 600;
    margin: 24px 0 12px;
}

.doc-body h4 {
    font-size: 16px;
    font-weight: 600;
    margin: 20px 0 10px;
}

.doc-body p {
    margin-bottom: 16px;
}

.doc-body ul, .doc-body ol {
    margin-bottom: 16px;
    padding-left: 24px;
}

.doc-body li {
    margin-bottom: 6px;
}

.doc-body code {
    background: #f1f5f9;
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
    font-family: 'SF Mono', 'Fira Code', monospace;
    color: #e11d48;
}

.doc-body pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 20px;
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin-bottom: 20px;
    font-size: 13px;
    line-height: 1.6;
}

.doc-body pre code {
    background: none;
    color: inherit;
    padding: 0;
}

.doc-body blockquote {
    border-left: 4px solid var(--primary);
    background: var(--primary-bg);
    padding: 14px 20px;
    margin-bottom: 20px;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.doc-body img {
    border-radius: var(--radius-md);
    margin: 16px 0;
    box-shadow: var(--shadow-md);
}

.doc-body a {
    color: var(--primary);
    text-decoration: underline;
    text-underline-offset: 3px;
}

.doc-body table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

.doc-body th, .doc-body td {
    border: 1px solid var(--border-color);
    padding: 10px 14px;
    text-align: left;
}

.doc-body th {
    background: var(--bg-body);
    font-weight: 600;
}

/* Doc Footer Nav */
.doc-footer-nav {
    margin-top: 48px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

.doc-back-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
}

.doc-back-btn:hover {
    background: var(--primary-bg);
    color: var(--primary);
    border-color: var(--primary-light);
}

/* ========================================
   Sidebar
   ======================================== */
.doc-sidebar-left,
.doc-sidebar-right {
    position: sticky;
    top: 96px;
}

.doc-sidebar-left {
    order: -1;
    max-width: 200px;
}

.doc-sidebar-right {
    max-width: 280px;
}

.doc-sidebar-left .sidebar-card,
.doc-sidebar-right .sidebar-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    margin-bottom: 20px;
}

.sidebar-toc-wrapper {
    max-height: 70vh;
    overflow-y: auto;
}

.sidebar-toc-wrapper .doc-toc {
    max-height: 70vh;
}

.sidebar-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 14px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.sidebar-docs, .sidebar-categories {
    list-style: none;
}

.sidebar-docs li, .sidebar-categories li {
    margin-bottom: 4px;
}

.sidebar-docs a, .sidebar-categories a {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 10px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    color: var(--text-secondary);
    transition: var(--transition);
}

.sidebar-docs a i, .sidebar-categories a i {
    font-size: 12px;
    color: var(--text-muted);
}

.sidebar-docs a:hover, .sidebar-categories a:hover {
    background: var(--primary-bg);
    color: var(--primary);
}

.sidebar-docs a.current, .sidebar-categories a.current {
    background: var(--primary-bg);
    color: var(--primary);
    font-weight: 500;
}

/* ========================================
   Search Page
   ======================================== */
.search-section {
    margin-bottom: 32px;
}

.search-title {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 20px;
}

.search-form {
    display: flex;
    align-items: center;
    gap: 10px;
    max-width: 600px;
    position: relative;
}

.search-form i.fa-search {
    position: absolute;
    left: 16px;
    color: var(--text-muted);
}

.search-input {
    width: 100%;
    padding: 12px 16px 12px 42px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 15px;
    font-family: var(--font-family);
    color: var(--text-primary);
    background: var(--bg-white);
    outline: none;
    transition: var(--transition);
}

.search-input:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.search-btn {
    position: absolute;
    right: 4px;
    padding: 8px 20px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    font-family: var(--font-family);
    cursor: pointer;
    transition: var(--transition);
}

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

.search-info {
    margin-top: 14px;
    font-size: 14px;
    color: var(--text-secondary);
}

.search-results {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.search-result-item {
    display: block;
    padding: 20px 24px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.search-result-item:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow-md);
}

.search-result-category {
    font-size: 12px;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.search-result-title {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text-primary);
}

.search-result-title mark {
    background: #fef08a;
    color: var(--text-primary);
    padding: 0 2px;
    border-radius: 2px;
}

.search-result-summary {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 8px;
}

.search-result-summary mark {
    background: #fef08a;
    color: var(--text-primary);
    padding: 0 2px;
    border-radius: 2px;
}

.search-result-snippet {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 8px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    /* autoprefixer: ignore next */
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.search-result-snippet mark {
    background: #fef08a;
    color: var(--text-primary);
    padding: 0 2px;
    border-radius: 2px;
}

.search-result-meta {
    display: flex;
    gap: 16px;
    font-size: 12px;
    color: var(--text-muted);
}

.search-result-meta i {
    margin-right: 3px;
}

/* ========================================
   Empty State
   ======================================== */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

.empty-state i {
    font-size: 48px;
    margin-bottom: 16px;
    display: block;
}

.empty-state p {
    font-size: 16px;
    margin-bottom: 20px;
}

.btn-back {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 24px;
    background: var(--primary);
    color: white;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
}

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

/* ========================================
   Pagination
   ======================================== */
.pagination {
    margin-top: 32px;
    display: flex;
    justify-content: center;
}

.pagination .pagination {
    gap: 4px;
}

.pagination li {
    list-style: none;
}

.pagination li a, .pagination li span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
    padding: 0 10px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--text-secondary);
    transition: var(--transition);
}

.pagination li a:hover {
    background: var(--primary-bg);
    color: var(--primary);
    border-color: var(--primary-light);
}

.pagination li.active span {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.pagination li.disabled span {
    color: var(--text-muted);
    cursor: not-allowed;
}

/* ========================================
   Reading Progress
   ======================================== */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    z-index: 1000;
    transition: width 0.1s linear;
}

/* ========================================
   Doc Search (文档内搜索)
   ======================================== */
.doc-search-input-wrap {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.doc-search-input {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-family: var(--font-family);
    color: var(--text-primary);
    background: var(--bg-body);
    outline: none;
    transition: var(--transition);
    box-sizing: border-box;
}

.doc-search-input:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    background: var(--bg-white);
}

.doc-search-actions {
    display: flex;
    align-items: center;
    gap: 4px;
    height: 28px;
}

.doc-search-info {
    font-size: 12px;
    color: var(--text-muted);
    min-width: 32px;
    flex: 1;
}

.doc-search-actions button {
    width: 28px;
    height: 28px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-white);
    color: var(--text-secondary);
    font-size: 11px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    padding: 0;
}

.doc-search-actions button:hover {
    background: var(--primary-bg);
    color: var(--primary);
    border-color: var(--primary-light);
}

/* 搜索结果高亮 */
.doc-search-highlight {
    background: #fef08a;
    color: var(--text-primary);
    padding: 0 2px;
    border-radius: 2px;
}

.doc-search-highlight.current {
    background: #f97316;
    color: white;
    padding: 0 3px;
}

/* ========================================
   Doc TOC (Table of Contents)
   ======================================== */
.doc-toc {
    font-size: 13px;
    line-height: 1.6;
}

.doc-toc-empty {
    color: var(--text-muted);
    font-size: 13px;
    padding: 8px 0;
}

.doc-toc ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.doc-toc li {
    margin: 0;
}

.doc-toc a {
    display: block;
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 13px;
    line-height: 1.5;
    transition: var(--transition);
    border-left: 2px solid transparent;
}

.doc-toc a:hover {
    background: var(--primary-bg);
    color: var(--primary);
}

.doc-toc a.active {
    background: var(--primary-bg);
    color: var(--primary);
    border-left-color: var(--primary);
    font-weight: 500;
}

.doc-toc .toc-h2 {
    font-weight: 500;
}

.doc-toc .toc-h3 {
    padding-left: 20px;
    font-size: 12px;
}

.doc-toc .toc-h4 {
    padding-left: 32px;
    font-size: 12px;
    color: var(--text-muted);
}

/* ========================================
   Code Copy Button
   ======================================== */
.code-block-wrapper {
    position: relative;
}

.code-copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    padding: 4px 10px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-sm);
    color: #94a3b8;
    font-size: 12px;
    font-family: var(--font-family);
    cursor: pointer;
    transition: var(--transition);
    opacity: 0;
    display: flex;
    align-items: center;
    gap: 4px;
}

.code-block-wrapper:hover .code-copy-btn {
    opacity: 1;
}

.code-copy-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    color: #e2e8f0;
}

.code-copy-btn.copied {
    background: rgba(34, 197, 94, 0.2);
    border-color: rgba(34, 197, 94, 0.4);
    color: #4ade80;
}

/* ========================================
   Image Lightbox
   ======================================== */
.lightbox-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
    padding: 40px;
}

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

.lightbox-overlay img {
    max-width: 100%;
    max-height: 100%;
    border-radius: var(--radius-md);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    transform: scale(0.9);
    transition: transform 0.3s ease;
}

.lightbox-overlay.active img {
    transform: scale(1);
}

.lightbox-close {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 50%;
    color: white;
    font-size: 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.lightbox-close:hover {
    background: rgba(255, 255, 255, 0.2);
}

.doc-body img {
    cursor: zoom-in;
    transition: transform 0.2s ease;
}

/* ========================================
   Anchor Links for Headings
   ======================================== */
.doc-body h1, .doc-body h2, .doc-body h3, .doc-body h4 {
    position: relative;
}

.doc-body .heading-anchor {
    position: absolute;
    left: -24px;
    top: 50%;
    transform: translateY(-50%);
    padding: 4px;
    color: var(--text-muted);
    font-size: 16px;
    text-decoration: none;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.doc-body h1:hover .heading-anchor,
.doc-body h2:hover .heading-anchor,
.doc-body h3:hover .heading-anchor,
.doc-body h4:hover .heading-anchor {
    opacity: 1;
}

.doc-body .heading-anchor:hover {
    color: var(--primary);
}

/* ========================================
   Print Styles
   ======================================== */
@media print {
    .header,
    .doc-sidebar-left,
    .doc-sidebar-right,
    .back-to-top,
    .reading-progress,
    .doc-footer-nav {
        display: none !important;
    }

    .doc-layout {
        display: block;
    }

    .doc-content {
        max-width: 100%;
    }

    .doc-body {
        font-size: 12pt;
        line-height: 1.6;
    }

    .doc-body pre {
        background: #f1f5f9 !important;
        color: #1e293b !important;
        border: 1px solid #e2e8f0;
        page-break-inside: avoid;
    }

    .doc-body a {
        color: #1e293b !important;
        text-decoration: underline;
    }

    .doc-body a[href]::after {
        content: " (" attr(href) ")";
        font-size: 10pt;
        color: #64748b;
    }

    .doc-body img {
        max-width: 100%;
        page-break-inside: avoid;
    }

    body {
        background: white;
    }

    .page-section {
        padding: 0;
    }
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background: var(--bg-white);
    border-top: 1px solid var(--border-color);
    padding: 36px 0;
    margin-top: auto;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    color: var(--text-primary);
}

.footer-brand i {
    color: var(--primary);
    font-size: 20px;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    font-size: 14px;
    color: var(--text-secondary);
}

.footer-links a:hover {
    color: var(--primary);
}

.footer-copy {
    font-size: 13px;
    color: var(--text-muted);
}

/* ========================================
   Back to Top
   ======================================== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 16px;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
    opacity: 0;
    visibility: hidden;
    z-index: 99;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 1280px) {
    .doc-layout {
        grid-template-columns: 180px 1fr 240px;
        gap: 24px;
    }

    .doc-sidebar-left {
        max-width: 180px;
    }

    .doc-sidebar-right {
        max-width: 240px;
    }
}

@media (max-width: 1024px) {
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .page-section:has(.doc-layout) > .container {
        max-width: var(--max-width);
    }

    .doc-layout {
        grid-template-columns: 160px 1fr 200px;
        gap: 20px;
    }

    .doc-sidebar-left {
        max-width: 160px;
    }

    .doc-sidebar-right {
        max-width: 200px;
    }
}

@media (max-width: 768px) {
    .header-inner {
        flex-wrap: wrap;
        height: auto;
        padding: 12px 0;
        gap: 12px;
    }

    .header-search {
        order: 3;
        max-width: 100%;
        width: 100%;
    }

    .header-nav {
        display: none;
    }

    .hero {
        padding: 48px 0 40px;
    }

    .hero-title {
        font-size: 24px;
    }

    .hero-search-input {
        padding: 14px 100px 14px 44px;
        font-size: 14px;
    }

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

    .category-card {
        padding: 20px;
    }

    .doc-title {
        font-size: 22px;
    }

    .doc-meta {
        flex-wrap: wrap;
        gap: 10px;
    }

    .doc-layout {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .doc-sidebar-left,
    .doc-sidebar-right {
        position: static;
        max-width: 100%;
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    .reading-progress {
        height: 2px;
    }

    .footer-inner {
        flex-direction: column;
        text-align: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}

/* ========================================
   Markdown Body Styles
   ======================================== */
.markdown-body {
    font-size: 15px;
    line-height: 1.8;
    color: var(--text-primary);
    word-wrap: break-word;
}

.markdown-body h1 {
    font-size: 26px;
    font-weight: 700;
    margin: 36px 0 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
}

.markdown-body h2 {
    font-size: 22px;
    font-weight: 600;
    margin: 30px 0 14px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-light);
}

.markdown-body h3 {
    font-size: 18px;
    font-weight: 600;
    margin: 24px 0 12px;
}

.markdown-body h4 {
    font-size: 16px;
    font-weight: 600;
    margin: 20px 0 10px;
}

.markdown-body h5 {
    font-size: 15px;
    font-weight: 600;
    margin: 18px 0 8px;
}

.markdown-body h6 {
    font-size: 14px;
    font-weight: 600;
    margin: 16px 0 8px;
    color: var(--text-secondary);
}

.markdown-body p {
    margin-bottom: 16px;
}

.markdown-body ul, .markdown-body ol {
    margin-bottom: 16px;
    padding-left: 24px;
}

.markdown-body li {
    margin-bottom: 6px;
}

.markdown-body li > ul, .markdown-body li > ol {
    margin-top: 6px;
    margin-bottom: 6px;
}

.markdown-body code {
    background: #f1f5f9;
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
    font-family: 'SF Mono', 'Fira Code', monospace;
    color: #e11d48;
}

.markdown-body pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 20px;
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin-bottom: 20px;
    font-size: 13px;
    line-height: 1.6;
}

.markdown-body pre code {
    background: none;
    color: inherit;
    padding: 0;
    font-size: inherit;
}

.markdown-body blockquote {
    border-left: 4px solid var(--primary);
    background: var(--primary-bg);
    padding: 14px 20px;
    margin: 0 0 20px 0;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    color: var(--text-secondary);
}

.markdown-body blockquote p:last-child {
    margin-bottom: 0;
}

.markdown-body img {
    border-radius: var(--radius-md);
    margin: 16px 0;
    box-shadow: var(--shadow-md);
    max-width: 100%;
}

.markdown-body a {
    color: var(--primary);
    text-decoration: underline;
    text-underline-offset: 3px;
}

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

.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
    overflow-x: auto;
    display: block;
}

.markdown-body thead {
    background: var(--bg-body);
}

.markdown-body th, .markdown-body td {
    border: 1px solid var(--border-color);
    padding: 10px 14px;
    text-align: left;
}

.markdown-body th {
    font-weight: 600;
}

.markdown-body hr {
    border: none;
    border-top: 2px solid var(--border-color);
    margin: 28px 0;
}

.markdown-body input[type="checkbox"] {
    margin-right: 6px;
}