/* ===== CSS Variables ===== */
:root {
    /* Colors */
    --primary-color: #9373EE;
    --primary-hover: #b499f4;
    --primary-active: #7a60c4;
    --primary-light: rgba(147, 115, 238, 0.1);
    --primary-light-hover: rgba(147, 115, 238, 0.15);

    --text-primary: #344054;
    --text-secondary: #667085;
    --text-tertiary: #98a2b3;
    --text-placeholder: #9ca3af;

    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f2f4f7;
    --bg-elevated: #ffffff;

    --border-color: #f2f4f7;
    --border-hover: #d0d5dd;
    --border-active: #9373EE;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

    /* Spacing */
    --header-height: 65px;
    --sidebar-width: 320px;
    --content-max-width: 1560px;
    --content-padding: 40px;

    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
    --font-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", Consolas, "Courier New", monospace;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;

    /* Z-index */
    --z-header: 100;
    --z-sidebar: 90;
    --z-dropdown: 200;
    --z-modal: 300;
    --z-toast: 400;
}

/* Dark Theme */
[data-theme="dark"] {
    --text-primary: #f2f4f7;
    --text-secondary: #d0d5dd;
    --text-tertiary: #98a2b3;
    --text-placeholder: #667085;

    --bg-primary: #1a1922;
    --bg-secondary: #23212a;
    --bg-tertiary: #2d2a36;
    --bg-elevated: #2d2a36;

    --border-color: #3d3a47;
    --border-hover: #4a4755;
    --border-active: #9373EE;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

/* Dark theme fallback */
[data-theme="dark"] .image-fallback {
    background-color: #23212a;
    border-color: #4a4755;
    color: #d0d5dd;
}

/* ===== Dark Code Blocks ===== */
.markdown-body pre {
    margin: 16px 0;
    padding: 20px;
    padding-top: 52px;
    background-color: #1e1e2e;
    border: 1px solid #3a3a4c;
    border-radius: 12px;
    overflow-x: auto;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    position: relative;
}

.code-copy-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 6px 10px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.08);
    color: #e2e8f0;
    font-size: 0.75rem;
    line-height: 1;
    transition: background-color 150ms ease, border-color 150ms ease, opacity 150ms ease;
    z-index: 1;
}

.code-copy-btn:hover {
    background: rgba(255, 255, 255, 0.14);
    border-color: rgba(255, 255, 255, 0.2);
}

.code-copy-btn.copied {
    background: rgba(147, 115, 238, 0.22);
    border-color: rgba(147, 115, 238, 0.55);
}

.markdown-body pre code {
    padding: 0;
    background: none;
    font-size: 0.8125rem;
    line-height: 1.6;
    color: #e2e8f0;
}

/* Code token colors */
.markdown-body pre .keyword {
    color: #c678dd;
}

.markdown-body pre .function {
    color: #61afef;
}

.markdown-body pre .string {
    color: #98c379;
}

.markdown-body pre .number {
    color: #d19a66;
}

.markdown-body pre .comment {
    color: #5c6370;
    font-style: italic;
}

.markdown-body pre .operator {
    color: #56b6c2;
}

.markdown-body pre .tag {
    color: #e06c75;
}

.markdown-body pre .attr {
    color: #e06c75;
}

.markdown-body pre .selector {
    color: #e06c75;
}

.markdown-body pre .class-name {
    color: #e5c07b;
}

/* ===== Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: var(--font-family);
    font-size: 1rem;
    line-height: 1.15;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    color: inherit;
}

ul, ol {
    list-style: none;
}

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

/* ===== Document Images ===== */
.markdown-body img {
    border-radius: 8px;
    margin: 16px 0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.markdown-body .image-container {
    margin: 24px 0;
    text-align: center;
}

.markdown-body .image-container img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.markdown-body .image-caption {
    margin-top: 8px;
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-style: italic;
}

/* Full-width banner images */
.markdown-body .banner-image {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: 12px;
    margin: 24px 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    background-color: var(--bg-secondary);
    min-height: 200px;
}

/* Image loading fallback */
.image-container img::before {
    content: '图片加载失败';
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-tertiary);
    font-size: 0.875rem;
}

.image-container {
    background-color: var(--bg-secondary);
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    position: relative;
    min-height: 200px;
}

.image-fallback {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 200px;
    border: 2px dashed var(--border-color);
    border-radius: 12px;
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    font-size: 0.875rem;
    text-align: center;
    line-height: 1.5;
    flex-direction: column;
    gap: 8px;
}

/* ===== App Container ===== */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* ===== Header ===== */
.header {
    position: sticky;
    top: 0;
    z-index: var(--z-header);
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: background var(--transition-base);
}

[data-theme="dark"] .header {
    background: rgba(26, 25, 34, 0.8);
}

.header-container {
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.header-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 24px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.125rem;
}

.brand-logo {
    width: 32px;
    height: 32px;
    border-radius: 8px;
}

.brand-name {
    color: var(--text-primary);
}

.nav-menu {
    display: flex;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    padding: 8px 12px;
    border-radius: 6px;
    transition: all var(--transition-fast);
}

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

.header-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.lang-switch {
    text-decoration: none;
}

.lang-btn {
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    color: white;
    background-color: var(--primary-color);
    transition: all var(--transition-fast);
}

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

.theme-toggle {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

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

/* ===== Main Layout ===== */
.main-layout {
    display: flex;
    flex: 1;
    max-width: 1560px;
    margin: 0 auto;
    width: 100%;
    gap: 0;
}

/* ===== Sidebar ===== */
.sidebar {
    width: var(--sidebar-width);
    min-width: var(--sidebar-width);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    height: calc(100vh - var(--header-height));
    position: sticky;
    top: var(--header-height);
    overflow-y: auto;
    background-color: var(--bg-secondary);
}

.sidebar-search {
    padding: 16px 20px;
}

.search-btn {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 14px;
    background-color: var(--bg-secondary);
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    transition: all var(--transition-fast);
}

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

.kbd {
    margin-left: auto;
    padding: 2px 6px;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 0.75rem;
    font-family: var(--font-mono);
    color: var(--text-tertiary);
    min-width: 36px;
    text-align: center;
}

.sidebar-nav {
    padding: 0 20px 20px;
}

.nav-section {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.nav-group {
    display: flex;
    flex-direction: column;
}

.nav-group-toggle {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.9375rem;
    border-radius: 8px;
    transition: all var(--transition-fast);
}

.nav-group-toggle:hover {
    background-color: var(--bg-secondary);
}

.nav-group-toggle.active .nav-icon {
    transform: rotate(180deg);
}

.nav-group-content {
    display: block;
    padding-left: 8px;
}

.nav-group-content.collapsed {
    display: none;
}

.nav-item {
    margin: 2px 0;
}

.nav-item-label {
    flex: 1;
    min-width: 0;
    text-align: left;
}

.nav-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 8px 12px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    border-radius: 6px;
    transition: all var(--transition-fast);
}

.nav-link-label {
    flex: 1;
    min-width: 0;
    line-height: 1.35;
}

.nav-method-badge {
    flex-shrink: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 34px;
    height: 18px;
    padding: 0 6px;
    border-radius: 6px;
    font-size: 0.6875rem;
    font-weight: 700;
    line-height: 1;
    letter-spacing: 0;
    color: #f97316;
    background: #fff3e8;
    border: 1px solid #fed7aa;
    margin-left: 8px;
}

.nav-method-badge[data-method="GET"] {
    color: #3b82f6;
    background: #eff6ff;
    border-color: #bfdbfe;
}

.nav-method-badge[data-method="DELETE"] {
    color: #dc2626;
    background: #fef2f2;
    border-color: #fecaca;
}

.nav-method-badge[data-method="PUT"],
.nav-method-badge[data-method="PATCH"] {
    color: #059669;
    background: #ecfdf5;
    border-color: #a7f3d0;
}

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

.nav-item.active .nav-link {
    color: var(--primary-color);
    background-color: var(--primary-light);
    font-weight: 500;
}

/* Nested menu items */
.nav-sub-items {
    display: block;
    max-height: 2000px;
    opacity: 1;
    transition: max-height 0.3s ease, opacity 0.3s ease, transform 0.3s ease;
    transform: scaleY(1);
    transform-origin: top;
    padding-left: 0;
    margin-left: 8px;
    border-left: 1px solid rgba(152, 162, 179, 0.18);
}

.nav-sub-items.collapsed {
    display: block;
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transform: scaleY(0);
    transform-origin: top;
}

.nav-item-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    padding: 8px 12px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    background: none;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    z-index: 10;
}

.nav-item-toggle[data-level="1"],
.nav-link[data-level="1"] {
    padding-left: 12px;
}

.nav-item-toggle[data-level="2"],
.nav-link[data-level="2"] {
    padding-left: 16px;
    font-size: 0.84375rem;
}

.nav-item-toggle[data-level="3"],
.nav-link[data-level="3"] {
    padding-left: 20px;
    font-size: 0.8125rem;
}

.nav-item-toggle[data-level="4"],
.nav-link[data-level="4"],
.nav-item-toggle[data-level="5"],
.nav-link[data-level="5"],
.nav-item-toggle[data-level="6"],
.nav-link[data-level="6"] {
    padding-left: 24px;
    font-size: 0.8125rem;
}

.nav-item-toggle:hover {
    color: var(--text-primary);
    background-color: var(--bg-secondary);
}

.nav-item-toggle.active {
    color: var(--primary-color);
    font-weight: 500;
    background-color: rgba(147, 115, 238, 0.08);
}

.nav-item.active .nav-item-toggle {
    color: var(--primary-color);
    background-color: var(--primary-light);
    font-weight: 500;
}

.nav-section-title {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.9375rem;
    border-radius: 8px;
    transition: all var(--transition-fast);
}

.nav-section-title:hover {
    color: var(--text-primary);
    background-color: var(--bg-secondary);
}

.nav-section-title.active {
    color: var(--primary-color);
    background-color: var(--primary-light);
    font-weight: 500;
}

.nav-icon {
    transition: transform var(--transition-fast);
    flex-shrink: 0;
}

.nav-sub-items .nav-item {
    position: relative;
}

.nav-sub-items .nav-item::before {
    content: '';
    position: absolute;
    left: -9px;
    top: 50%;
    width: 8px;
    height: 1px;
    background: rgba(152, 162, 179, 0.22);
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    min-width: 0;
    padding: 0;
    background-color: var(--bg-primary);
}

.mobile-header {
    display: none;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color);
}

.mobile-menu-toggle {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-primary);
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.breadcrumb svg {
    width: 14px;
    height: 14px;
}

.mobile-actions {
    margin-left: auto;
}

.icon-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

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

.page-content {
    padding: 0;
    max-width: none;
}

.markdown-body {
    padding: 0 var(--content-padding);
    max-width: 720px;
    margin: 0 auto;
}

.content-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.breadcrumb.desktop {
    display: flex;
}

.header-actions {
    display: flex;
    gap: 8px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.btn svg {
    width: 14px;
    height: 14px;
}

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

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

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

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

/* ===== Page Title ===== */
.page-title {
    font-size: 2rem;
    font-weight: 600;
    line-height: 1.25;
    color: var(--text-primary);
    margin-bottom: 32px;
}

/* ===== Markdown Body ===== */
.markdown-body {
    color: var(--text-primary);
}

.hero-section {
    text-align: left;
    margin-bottom: 40px;
    padding: 40px 0;
    border-bottom: 1px solid var(--border-color);
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-primary);
    line-height: 1.2;
}

.hero-title .anchor {
    opacity: 0;
    color: var(--text-tertiary);
    margin-left: 12px;
    font-weight: normal;
    transition: color var(--transition-fast);
}

.hero-title:hover .anchor {
    color: var(--primary-color);
}

.hero-text {
    font-size: 1.125rem;
    line-height: 1.6;
    color: var(--text-secondary);
    max-width: none;
}

/* ===== Feature Cards ===== */
.feature-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
    margin-bottom: 48px;
}

.feature-card {
    padding: 24px;
    border: 1px solid var(--border-color);
    border-top: 4px solid transparent;
    border-radius: 12px;
    background-color: var(--bg-elevated);
    transition: all var(--transition-base);
    color: var(--text-primary);
}

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

/* First card - purple */
.feature-card:nth-child(1) {
    border-top-color: #8B5CF6;
}

/* Second card - green */
.feature-card:nth-child(2) {
    border-top-color: #10B981;
}

/* Third card - orange */
.feature-card:nth-child(3) {
    border-top-color: #F59E0B;
}

.feature-card h2 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.feature-card p {
    font-size: 0.875rem;
    line-height: 1.6;
    color: var(--text-secondary);
}

/* ===== Folder Grid ===== */
.folder-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
    margin-bottom: 48px;
}

.folder-item {
    display: block;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    transition: all var(--transition-base);
    color: var(--text-primary);
    text-decoration: none;
}

.folder-item:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.folder-item-content {
    padding: 20px;
}

.folder-item h3 {
    font-size: 1rem;
    font-weight: 600;
    margin: 0 0 8px 0;
    color: var(--text-primary);
    line-height: 1.5;
}

.folder-item p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin: 0;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ===== Headings ===== */
.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4 {
    position: relative;
}

.markdown-body h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin: 40px 0 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-primary);
}

.markdown-body h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin: 32px 0 12px;
    color: var(--text-primary);
}

.markdown-body h4 {
    font-size: 1.0625rem;
    font-weight: 600;
    margin: 24px 0 8px;
    color: var(--text-primary);
}

.markdown-body .anchor {
    position: absolute;
    left: -24px;
    top: 0;
    opacity: 0;
    color: var(--text-tertiary);
    font-weight: normal;
    font-size: 1rem;
    transition: opacity var(--transition-fast);
    text-decoration: none;
}

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

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

.markdown-body p {
    font-size: 1rem;
    line-height: 1.75;
    margin-bottom: 16px;
    color: var(--text-secondary);
}

.markdown-body ul,
.markdown-body ol {
    margin: 16px 0 24px;
    padding-left: 24px;
}

.markdown-body ul {
    list-style: disc;
}

.markdown-body ol {
    list-style: decimal;
}

.markdown-body li {
    margin-bottom: 8px;
    line-height: 1.75;
    color: var(--text-secondary);
}

.markdown-body strong {
    font-weight: 600;
    color: var(--text-primary);
}

.markdown-body code {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    padding: 2px 6px;
    background-color: var(--bg-tertiary);
    border-radius: 4px;
    color: var(--primary-color);
}

.markdown-body pre {
    margin: 16px 0;
    padding: 20px;
    background-color: #1e1e2e;
    border: 1px solid #3a3a4c;
    border-radius: 12px;
    overflow-x: auto;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.markdown-body pre code {
    padding: 0;
    background: none;
    font-size: 0.8125rem;
    line-height: 1.6;
    color: #e2e8f0;
}

.markdown-body a code {
    color: var(--primary-color);
    background-color: var(--primary-light);
}

.markdown-body a code:hover {
    background-color: var(--primary-light-hover);
}

.markdown-body hr {
    margin: 40px 0;
    border: none;
    border-top: 1px solid var(--border-color);
}

.markdown-body .note {
    padding: 16px 20px;
    background-color: var(--primary-light);
    border-left: 4px solid var(--primary-color);
    border-radius: 0 8px 8px 0;
    margin: 24px 0;
    line-height: 1.6;
    color: var(--text-primary);
}

/* ===== Right Sidebar TOC ===== */
.toc-sidebar {
    width: 280px;
    min-width: 280px;
    padding: 20px;
    border-left: 1px solid var(--border-color);
    height: calc(100vh - var(--header-height));
    position: sticky;
    top: var(--header-height);
    overflow-y: auto;
    background-color: var(--bg-secondary);
}

.toc-sidebar .toc {
    margin: 0;
    padding: 0;
    background: none;
    border: none;
}

.toc-sidebar .toc h4 {
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

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

.toc-sidebar .toc li {
    margin-bottom: 4px;
}

.toc-sidebar .toc a {
    display: block;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
    line-height: 1.4;
}

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

.toc-sidebar .toc a.active {
    color: var(--primary-color);
    font-weight: 500;
    background-color: var(--primary-light);
}

.toc-sidebar .toc a {
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.toc-sidebar .toc a:active {
    color: var(--primary-color);
}

.toc-sidebar .toc .toc-h2 {
    padding-left: 0;
}

.toc-sidebar .toc .toc-h3 {
    padding-left: 16px;
}

.toc-sidebar .toc .toc-h4 {
    padding-left: 24px;
}

/* ===== Legacy TOC for mobile/fallback ===== */
.toc {
    margin-top: 48px;
    padding: 20px;
    background-color: var(--bg-secondary);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.toc h4 {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

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

.toc li {
    margin: 4px 0;
}

.toc a {
    display: block;
    padding: 6px 0;
    font-size: 0.875rem;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.toc a:hover {
    color: var(--primary-color);
    padding-left: 4px;
}

/* ===== Page Footer ===== */
.page-footer {
    margin-top: 48px;
    padding-top: 32px;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.prev-page-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 20px;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    transition: all var(--transition-base);
    order: -1;
}

.prev-page-link:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    transform: translateX(-4px);
}

.prev-page-link svg {
    width: 16px;
    height: 16px;
}

.prev-page-link span:first-child {
    font-size: 0.875rem;
    color: var(--text-tertiary);
}

.prev-page-link span:nth-child(2) {
    font-weight: 600;
    font-size: 1rem;
}

.next-page-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 20px;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

.next-page-link:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    transform: translateX(4px);
}

.next-page-link span:first-child {
    font-size: 0.875rem;
    color: var(--text-tertiary);
}

.next-page-link span:nth-child(2) {
    font-weight: 600;
    font-size: 1rem;
}

.next-page-link svg {
    margin-left: auto;
    width: 16px;
    height: 16px;
}

/* ===== Footer ===== */
.footer {
    padding: 20px 40px;
    border-top: 1px solid var(--border-color);
}

.llms-link {
    text-decoration: none;
}

.llms-link button {
    padding: 8px 16px;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 0.875rem;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

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

/* ===== Responsive ===== */
@media (max-width: 1200px) {
    .toc-sidebar {
        display: none;
    }
}

@media (max-width: 1024px) {
    .sidebar {
        position: fixed;
        left: -100%;
        top: var(--header-height);
        z-index: var(--z-sidebar);
        transition: left var(--transition-base);
        background-color: var(--bg-primary);
        border-right: 1px solid var(--border-color);
    }

    .sidebar.open {
        left: 0;
    }

    .sidebar-overlay {
        display: none;
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: calc(var(--z-sidebar) - 1);
    }

    .sidebar-overlay.open {
        display: block;
    }

    .main-layout {
        display: block;
    }

    .mobile-header {
        display: flex;
    }

    .content-header {
        display: none;
    }

    .page-content {
        padding: 24px 20px;
    }
}

@media (max-width: 640px) {
    .header-left {
        gap: 12px;
    }

    .nav-menu {
        display: none;
    }

    .brand-name {
        font-size: 1rem;
    }

    .lang-btn {
        padding: 6px 12px;
        font-size: 0.8125rem;
    }

    .page-title {
        font-size: 1.5rem;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-text {
        font-size: 1rem;
    }

    .feature-cards {
        grid-template-columns: 1fr;
    }
}

/* ===== Scrollbar ===== */
.sidebar::-webkit-scrollbar {
    width: 6px;
}

.sidebar::-webkit-scrollbar-track {
    background: transparent;
}

.sidebar::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.sidebar::-webkit-scrollbar-thumb:hover {
    background: var(--border-hover);
}

/* ===== Selection ===== */
::selection {
    background-color: var(--primary-light);
    color: var(--text-primary);
}

/* ===== Focus States ===== */
a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}