/* ========================================
   玄晶引擎学习中心 - 全局样式
   技术栈: 纯HTML + CSS + JavaScript
   ======================================== */

/* CSS变量定义 */
:root {
  /* 主色调 */
  --tech-dark: #0A192F;
  --tech-card: #112240;
  --tech-border: #233554;
  --tech-accent: #64FFDA;
  --tech-text: #CCD6F6;
  --tech-muted: #8892B0;
  --tech-dim: #5F6B8A;
  
  /* 功能色 */
  --success: #4CAF50;
  --warning: #FFC107;
  --error: #F44336;
  
  /* 间距系统 */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 64px;
  --space-2xl: 80px;
  
  /* 尺寸 */
  --nav-height: 80px;
  --nav-height-mobile: 60px;
  --max-width: 1200px;
  
  /* 动画 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* 重置样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  background-color: var(--tech-dark);
  color: var(--tech-text);
  line-height: 1.6;
  min-height: 100vh;
}

a {
  text-decoration: none;
  color: inherit;
}

ul, ol {
  list-style: none;
}

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

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

input, textarea {
  font-family: inherit;
}

/* 选中样式 */
::selection {
  background: rgba(100, 255, 218, 0.3);
  color: var(--tech-text);
}

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

::-webkit-scrollbar-track {
  background: var(--tech-dark);
}

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

::-webkit-scrollbar-thumb:hover {
  background: var(--tech-accent);
}

/* ========================================
   通用组件样式
   ======================================== */

/* 玻璃拟态 */
.glass {
  background: rgba(10, 25, 47, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

/* 容器 */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* 卡片 - 带辉光效果 */
.tech-card {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  transition: all var(--transition-normal);
}

.tech-card:hover {
  border-color: var(--tech-accent);
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.12);
  transform: translateY(-4px);
}

/* 按钮 */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  background: var(--tech-accent);
  color: var(--tech-dark);
  font-weight: 600;
  padding: 12px 24px;
  border-radius: 8px;
  transition: all var(--transition-normal);
}

.btn-primary:hover {
  filter: brightness(1.15);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(100, 255, 218, 0.3);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  border: 1px solid var(--tech-accent);
  color: var(--tech-accent);
  font-weight: 600;
  padding: 12px 24px;
  border-radius: 8px;
  background: transparent;
  transition: all var(--transition-normal);
}

.btn-secondary:hover {
  background: var(--tech-accent);
  color: var(--tech-dark);
}

/* 输入框 */
.tech-input {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 8px;
  padding: 12px 16px;
  color: var(--tech-text);
  width: 100%;
  transition: all var(--transition-normal);
  font-size: 14px;
}

.tech-input::placeholder {
  color: var(--tech-dim);
}

.tech-input:focus {
  outline: none;
  border-color: var(--tech-accent);
  box-shadow: 0 0 0 3px rgba(100, 255, 218, 0.1);
}

/* 标签 */
.tech-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  background: rgba(100, 255, 218, 0.1);
  color: var(--tech-accent);
  font-size: 12px;
  font-weight: 500;
  border-radius: 4px;
}

/* 链接 */
.tech-link {
  color: var(--tech-muted);
  transition: color var(--transition-normal);
}

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

/* 代码块 */
.code-block {
  background: var(--tech-dark);
  border: 1px solid var(--tech-border);
  border-radius: 8px;
  padding: 16px;
  font-family: 'Fira Code', 'Consolas', monospace;
  font-size: 14px;
  overflow-x: auto;
  color: var(--tech-muted);
}

/* 分页 */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  margin-top: var(--space-xl);
}

.pagination button,
.pagination span {
  padding: 10px 18px;
  border-radius: 8px;
  font-size: 14px;
  transition: all var(--transition-normal);
}

.pagination button {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
}

.pagination button:hover {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
}

.pagination span.active {
  background: var(--tech-accent);
  color: var(--tech-dark);
  font-weight: 600;
}

.pagination span:not(.active) {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  cursor: pointer;
}

.pagination span:not(.active):hover {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
}

/* ========================================
   导航栏
   ======================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  border-bottom: 1px solid transparent;
  transition: all var(--transition-normal);
}

.navbar.scrolled {
  background: rgba(10, 25, 47, 0.95);
  backdrop-filter: blur(12px);
  border-bottom-color: var(--tech-border);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.navbar-logo img {
  height: 40px;
  width: auto;
}

.navbar-menu {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.navbar-menu a {
  position: relative;
  color: var(--tech-muted);
  font-size: 14px;
  font-weight: 500;
  transition: color var(--transition-normal);
  padding: var(--space-xs) 0;
}

.navbar-menu a:hover,
.navbar-menu a.active {
  color: var(--tech-accent);
}

.navbar-menu a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--tech-accent);
  transition: width var(--transition-normal);
}

.navbar-menu a:hover::after,
.navbar-menu a.active::after {
  width: 100%;
}

.navbar-right {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.navbar-search {
  position: relative;
}

.navbar-search input {
  width: 260px;
  padding-right: 40px;
}

.navbar-search button {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--tech-dim);
  transition: color var(--transition-normal);
}

.navbar-search button:hover {
  color: var(--tech-accent);
}

.navbar-login {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 10px 18px;
  border: 1px solid var(--tech-accent);
  color: var(--tech-accent);
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition-normal);
}

.navbar-login:hover {
  background: var(--tech-accent);
  color: var(--tech-dark);
}

.navbar-toggle {
  display: none;
  color: var(--tech-text);
  padding: var(--space-xs);
}

/* ========================================
   轮播
   ======================================== */

.hero-carousel {
  position: relative;
  width: 100%;
  height: 500px;
  overflow: hidden;
}

.carousel-container {
  display: flex;
  height: 100%;
  transition: transform 0.5s ease;
}

.carousel-slide {
  min-width: 100%;
  height: 100%;
  position: relative;
}

.carousel-slide .bg-image {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
}

.carousel-slide .overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to right, rgba(10, 25, 47, 0.92), rgba(10, 25, 47, 0.6));
}

.carousel-slide .content {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
}

.carousel-slide h1 {
  font-size: 48px;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-md);
  line-height: 1.2;
}

.carousel-slide p {
  font-size: 20px;
  color: var(--tech-muted);
  margin-bottom: var(--space-lg);
  max-width: 600px;
}

.carousel-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(17, 34, 64, 0.8);
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-normal);
  cursor: pointer;
}

.carousel-nav:hover {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
  background: rgba(17, 34, 64, 1);
}

.carousel-nav.prev {
  left: var(--space-md);
}

.carousel-nav.next {
  right: var(--space-md);
}

.carousel-dots {
  position: absolute;
  bottom: var(--space-lg);
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: var(--space-xs);
}

.carousel-dots button {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--tech-border);
  transition: all var(--transition-normal);
}

.carousel-dots button.active {
  background: var(--tech-accent);
  width: 32px;
  border-radius: 6px;
}

.carousel-dots button:hover {
  background: var(--tech-accent);
}

/* ========================================
   页面头部 - 带渐变背景
   ======================================== */

.page-header {
  padding: var(--space-2xl) 0 var(--space-xl);
  background: linear-gradient(180deg, rgba(17, 34, 64, 0.6) 0%, var(--tech-dark) 100%);
  margin-bottom: var(--space-lg);
}

.page-header .breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: var(--space-lg);
}

.page-header .breadcrumb a:hover {
  color: var(--tech-accent);
}

.page-header .breadcrumb .current {
  color: var(--tech-text);
}

.page-header h1 {
  font-size: 36px;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-sm);
}

.page-header p {
  color: var(--tech-muted);
  font-size: 16px;
}

/* ========================================
   板块入口卡片 - 首页
   ======================================== */

.section-cards {
  padding: var(--space-2xl) 0;
}

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

.section-header h2 {
  font-size: 32px;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-sm);
}

.section-header p {
  color: var(--tech-muted);
  max-width: 600px;
  margin: 0 auto;
}

.section-cards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
}

.section-card {
  display: block;
  padding: var(--space-lg);
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  transition: all var(--transition-normal);
}

.section-card:hover {
  border-color: var(--tech-accent);
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.12);
  transform: translateY(-4px);
}

.section-card .icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
}

.section-card .icon.blue {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.2), rgba(6, 182, 212, 0.2));
}

.section-card .icon.green {
  background: linear-gradient(135deg, rgba(34, 197, 94, 0.2), rgba(16, 185, 129, 0.2));
}

.section-card .icon.purple {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.2), rgba(236, 72, 153, 0.2));
}

.section-card .icon.orange {
  background: linear-gradient(135deg, rgba(249, 115, 22, 0.2), rgba(234, 179, 8, 0.2));
}

.section-card .icon svg {
  width: 28px;
  height: 28px;
  color: var(--tech-accent);
}

.section-card h3 {
  font-size: 20px;
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-sm);
  transition: color var(--transition-normal);
}

.section-card:hover h3 {
  color: var(--tech-accent);
}

.section-card p {
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: var(--space-md);
  line-height: 1.6;
}

.section-card .footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.section-card .footer svg {
  width: 20px;
  height: 20px;
  color: var(--tech-muted);
  transition: all var(--transition-normal);
}

.section-card:hover .footer svg {
  color: var(--tech-accent);
  transform: translateX(4px);
}

/* ========================================
   筛选标签
   ======================================== */

.filter-section {
  margin-bottom: var(--space-lg);
}

.filter-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

.filter-tab {
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  transition: all var(--transition-normal);
  cursor: pointer;
}

.filter-tab:hover {
  color: var(--tech-accent);
  border-color: var(--tech-accent);
}

.filter-tab.active {
  background: var(--tech-accent);
  border-color: var(--tech-accent);
  color: var(--tech-dark);
}

/* ========================================
   文档卡片 - 列表页
   ======================================== */

.docs-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.doc-card {
  display: block;
  padding: var(--space-lg);
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  transition: all var(--transition-normal);
}

.doc-card:hover {
  border-color: var(--tech-accent);
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.12);
  transform: translateY(-4px);
}

.doc-card .header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-md);
}

.doc-card .icon {
  width: 48px;
  height: 48px;
  border-radius: 8px;
  background: rgba(100, 255, 218, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
}

.doc-card .icon svg {
  width: 24px;
  height: 24px;
  color: var(--tech-accent);
}

.doc-card h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-sm);
  line-height: 1.4;
  transition: color var(--transition-normal);
}

.doc-card:hover h3 {
  color: var(--tech-accent);
}

.doc-card p {
  font-size: 14px;
  color: var(--tech-muted);
  line-height: 1.6;
  margin-bottom: var(--space-md);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.doc-card .meta {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid var(--tech-border);
  font-size: 12px;
  color: var(--tech-dim);
}

.doc-card .meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.doc-card .meta svg {
  width: 14px;
  height: 14px;
}

/* ========================================
   视频卡片 - 列表页
   ======================================== */

.videos-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.video-card {
  display: block;
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  overflow: hidden;
  transition: all var(--transition-normal);
}

.video-card:hover {
  border-color: var(--tech-accent);
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.12);
  transform: translateY(-4px);
}

.video-card .thumbnail {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
}

.video-card .thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.video-card:hover .thumbnail img {
  transform: scale(1.08);
}

.video-card .thumbnail .play-overlay {
  position: absolute;
  inset: 0;
  background: rgba(10, 25, 47, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.video-card:hover .thumbnail .play-overlay {
  opacity: 1;
}

.video-card .thumbnail .play-overlay .play-btn {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: rgba(100, 255, 218, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-normal);
}

.video-card .thumbnail .play-overlay .play-btn:hover {
  background: rgba(100, 255, 218, 0.35);
  transform: scale(1.1);
}

.video-card .thumbnail .play-overlay .play-btn svg {
  width: 28px;
  height: 28px;
  color: var(--tech-accent);
  fill: var(--tech-accent);
  margin-left: 4px;
}

.video-card .thumbnail .duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  padding: 4px 8px;
  background: rgba(10, 25, 47, 0.85);
  border-radius: 4px;
  font-size: 12px;
  font-family: monospace;
  color: #fff;
}

.video-card .thumbnail .category {
  position: absolute;
  top: 8px;
  left: 8px;
}

.video-card .content {
  padding: var(--space-md);
}

.video-card h3 {
  font-size: 15px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-sm);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: color var(--transition-normal);
}

.video-card:hover h3 {
  color: var(--tech-accent);
}

.video-card .meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--tech-dim);
}

.video-card .meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.video-card .meta svg {
  width: 14px;
  height: 14px;
}

/* ========================================
   API列表
   ======================================== */

.api-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.api-item {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  overflow: hidden;
  transition: all var(--transition-normal);
}

.api-item:hover {
  border-color: var(--tech-accent);
}

.api-item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  cursor: pointer;
  transition: background var(--transition-normal);
}

.api-item-header:hover {
  background: rgba(100, 255, 218, 0.03);
}

.api-item-header .left {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.api-method {
  padding: 6px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-family: monospace;
  font-weight: 600;
}

.api-method.get {
  background: rgba(34, 197, 94, 0.15);
  color: #4ade80;
}

.api-method.post {
  background: rgba(59, 130, 246, 0.15);
  color: #60a5fa;
}

.api-method.put {
  background: rgba(234, 179, 8, 0.15);
  color: #facc15;
}

.api-method.delete {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
}

.api-item-header .info h4 {
  font-family: monospace;
  font-size: 14px;
  color: var(--tech-text);
  margin-bottom: 4px;
}

.api-item-header .info p {
  font-size: 13px;
  color: var(--tech-muted);
}

.api-item-header .right {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.api-item-header .version {
  font-size: 12px;
  color: var(--tech-dim);
}

.api-item-header .toggle {
  width: 24px;
  height: 24px;
  color: var(--tech-muted);
  transition: transform var(--transition-normal);
}

.api-item.expanded .api-item-header .toggle {
  transform: rotate(180deg);
}

.api-item-content {
  display: none;
  padding: var(--space-lg);
  border-top: 1px solid var(--tech-border);
}

.api-item.expanded .api-item-content {
  display: block;
}

.api-item-content h5 {
  font-size: 14px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-sm);
}

.api-endpoint {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.api-endpoint code {
  flex: 1;
  color: var(--tech-accent);
  font-family: monospace;
  font-size: 13px;
}

.api-endpoint .copy-btn {
  padding: 10px;
  border-radius: 8px;
  background: var(--tech-dark);
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  transition: all var(--transition-normal);
}

.api-endpoint .copy-btn:hover {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
}

.api-params {
  margin-bottom: var(--space-lg);
}

.api-params table {
  width: 100%;
  font-size: 13px;
  border-collapse: collapse;
}

.api-params th,
.api-params td {
  text-align: left;
  padding: 12px;
  border-bottom: 1px solid var(--tech-border);
}

.api-params th {
  color: var(--tech-muted);
  font-weight: 500;
}

.api-params td {
  color: var(--tech-text);
}

.api-params td.name {
  font-family: monospace;
  color: var(--tech-accent);
}

.api-params td.required {
  color: #f87171;
}

.api-params td.optional {
  color: var(--tech-dim);
}

.api-response pre {
  color: var(--tech-muted);
  font-size: 13px;
}

/* ========================================
   FAQ列表
   ======================================== */

.faq-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.faq-item {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  overflow: hidden;
  transition: all var(--transition-normal);
}

.faq-item:hover {
  border-color: var(--tech-accent);
}

.faq-item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  cursor: pointer;
  transition: background var(--transition-normal);
}

.faq-item-header:hover {
  background: rgba(100, 255, 218, 0.03);
}

.faq-item-header h4 {
  font-size: 15px;
  font-weight: 500;
  color: var(--tech-text);
  flex: 1;
  padding-right: var(--space-md);
}

.faq-item-header .meta {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.faq-item-header .views {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--tech-dim);
}

.faq-item-header .toggle {
  width: 20px;
  height: 20px;
  color: var(--tech-muted);
  transition: transform var(--transition-normal);
}

.faq-item.expanded .faq-item-header .toggle {
  transform: rotate(180deg);
}

.faq-item-content {
  display: none;
  padding: 0 var(--space-lg) var(--space-lg);
  border-top: 1px solid var(--tech-border);
}

.faq-item.expanded .faq-item-content {
  display: block;
}

.faq-item-content p {
  color: var(--tech-muted);
  line-height: 1.8;
  padding-top: var(--space-md);
}

.faq-item-content .footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid rgba(35, 53, 84, 0.5);
  font-size: 12px;
  color: var(--tech-dim);
}

/* ========================================
   侧边栏 - 栏目页
   ======================================== */

.content-with-sidebar {
  display: flex;
  gap: var(--space-xl);
}

.main-content {
  flex: 1;
}

.sidebar {
  width: 280px;
  flex-shrink: 0;
}

.sidebar-sticky {
  position: sticky;
  top: 100px;
}

.sidebar-card {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  padding: var(--space-lg);
  margin-bottom: var(--space-md);
}

.sidebar-card h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-md);
}

.sidebar-menu {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sidebar-menu a {
  display: block;
  padding: 10px 12px;
  border-radius: 6px;
  font-size: 14px;
  color: var(--tech-muted);
  transition: all var(--transition-normal);
}

.sidebar-menu a:hover {
  background: rgba(100, 255, 218, 0.05);
  color: var(--tech-text);
}

.sidebar-menu a.active {
  background: rgba(100, 255, 218, 0.1);
  color: var(--tech-accent);
}

/* ========================================
   文档详情页
   ======================================== */

.doc-detail-layout {
  display: flex;
  gap: var(--space-xl);
}

.doc-detail-main {
  flex: 1;
}

.doc-detail-sidebar {
  width: 300px;
  flex-shrink: 0;
}

.doc-content {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  padding: var(--space-xl);
}

.doc-content h2 {
  font-size: 24px;
  font-weight: 600;
  color: #fff;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
}

.doc-content h2:first-child {
  margin-top: 0;
}

.doc-content h3 {
  font-size: 20px;
  font-weight: 600;
  color: var(--tech-text);
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
}

.doc-content p {
  font-size: 15px;
  color: var(--tech-muted);
  line-height: 1.8;
  margin-bottom: var(--space-md);
}

.doc-content ul {
  list-style: disc;
  padding-left: var(--space-lg);
  margin-bottom: var(--space-md);
}

.doc-content ul li {
  font-size: 15px;
  color: var(--tech-muted);
  line-height: 1.8;
  margin-bottom: var(--space-xs);
}

.doc-content pre {
  margin-bottom: var(--space-md);
}

.doc-content .faq-box {
  background: var(--tech-dark);
  border: 1px solid var(--tech-border);
  border-radius: 8px;
  padding: var(--space-md);
  margin-bottom: var(--space-sm);
}

.doc-content .faq-box p {
  margin-bottom: var(--space-xs);
}

.doc-content .faq-box p:last-child {
  margin-bottom: 0;
}

.doc-content .faq-box .q {
  font-weight: 500;
  color: var(--tech-text);
}

.doc-content .faq-box .a {
  font-size: 14px;
}

.doc-content .resource-links {
  list-style: none;
  padding-left: 0;
}

.doc-content .resource-links li {
  margin-bottom: var(--space-xs);
}

.doc-content .resource-links a {
  color: var(--tech-accent);
  transition: opacity var(--transition-normal);
}

.doc-content .resource-links a:hover {
  opacity: 0.8;
}

.doc-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--tech-border);
}

.doc-nav a {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 14px;
  color: var(--tech-muted);
  transition: color var(--transition-normal);
}

.doc-nav a:hover {
  color: var(--tech-accent);
}

.doc-nav a svg {
  width: 16px;
  height: 16px;
}

/* ========================================
   视频播放页
   ======================================== */

.video-player-section {
  background: #000;
}

.video-player-container {
  max-width: 1000px;
  margin: 0 auto;
}

.video-player {
  position: relative;
  aspect-ratio: 16 / 9;
  background: var(--tech-card);
  display: flex;
  align-items: center;
  justify-content: center;
}

.video-player img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.5;
}

.video-player .play-btn {
  position: relative;
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: rgba(100, 255, 218, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-normal);
}

.video-player .play-btn:hover {
  background: rgba(100, 255, 218, 0.35);
  transform: scale(1.1);
}

.video-player .play-btn svg {
  width: 36px;
  height: 36px;
  color: var(--tech-accent);
  fill: var(--tech-accent);
  margin-left: 4px;
}

.video-player-controls {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: var(--space-md);
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.video-player-controls button {
  color: #fff;
  transition: color var(--transition-normal);
}

.video-player-controls button:hover {
  color: var(--tech-accent);
}

.video-player-controls .progress-bar {
  flex: 1;
  height: 4px;
  background: rgba(255, 255, 255, 0.3);
  border-radius: 2px;
  overflow: hidden;
}

.video-player-controls .progress-bar .progress {
  width: 33%;
  height: 100%;
  background: var(--tech-accent);
}

.video-player-controls .time {
  font-size: 13px;
  font-family: monospace;
  color: #fff;
}

.video-info-section {
  padding: var(--space-lg) 0;
}

.video-info-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-lg);
  margin-bottom: var(--space-lg);
}

.video-info-header h1 {
  font-size: 24px;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-sm);
}

.video-info-header .meta {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  font-size: 14px;
  color: var(--tech-dim);
}

.video-info-header .meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.video-info-header .meta svg {
  width: 16px;
  height: 16px;
}

.video-actions {
  display: flex;
  gap: var(--space-sm);
}

.video-actions button {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition-normal);
}

.video-actions .btn-like {
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  background: transparent;
}

.video-actions .btn-like:hover,
.video-actions .btn-like.active {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
  background: rgba(100, 255, 218, 0.1);
}

.video-actions .btn-share {
  border: 1px solid var(--tech-border);
  color: var(--tech-muted);
  background: transparent;
}

.video-actions .btn-share:hover {
  border-color: var(--tech-accent);
  color: var(--tech-accent);
}

.video-content-layout {
  display: flex;
  gap: var(--space-xl);
}

.video-main {
  flex: 1;
}

.video-description {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
}

.video-description h3 {
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-md);
}

.video-description p {
  font-size: 14px;
  color: var(--tech-muted);
  line-height: 1.7;
  margin-bottom: var(--space-md);
}

.video-description h4 {
  font-size: 14px;
  font-weight: 500;
  color: var(--tech-text);
  margin-bottom: var(--space-sm);
}

.video-description ul {
  list-style: disc;
  padding-left: var(--space-lg);
}

.video-description ul li {
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: 4px;
}

.video-comments {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  padding: var(--space-lg);
}

.video-comments h3 {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-lg);
}

.video-comments h3 svg {
  width: 18px;
  height: 18px;
  color: var(--tech-accent);
}

.comment-input {
  display: flex;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}

.comment-input .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(100, 255, 218, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.comment-input .avatar svg {
  width: 20px;
  height: 20px;
  color: var(--tech-accent);
}

.comment-input .input-area {
  flex: 1;
}

.comment-input textarea {
  width: 100%;
  height: 100px;
  resize: none;
  margin-bottom: var(--space-sm);
}

.comment-input .submit-btn {
  display: flex;
  justify-content: flex-end;
}

.comment-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.comment-item {
  display: flex;
  gap: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--tech-border);
}

.comment-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.comment-item .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(100, 255, 218, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.comment-item .avatar span {
  font-size: 14px;
  font-weight: 600;
  color: var(--tech-accent);
}

.comment-item .content {
  flex: 1;
}

.comment-item .content .header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xs);
}

.comment-item .content .header .name {
  font-size: 14px;
  font-weight: 500;
  color: var(--tech-text);
}

.comment-item .content .header .time {
  font-size: 12px;
  color: var(--tech-dim);
}

.comment-item .content p {
  font-size: 14px;
  color: var(--tech-muted);
  line-height: 1.5;
  margin-bottom: var(--space-xs);
}

.comment-item .content .actions {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--tech-dim);
}

.comment-item .content .actions button {
  display: flex;
  align-items: center;
  gap: 4px;
  transition: color var(--transition-normal);
}

.comment-item .content .actions button:hover {
  color: var(--tech-accent);
}

.comment-item .content .actions svg {
  width: 14px;
  height: 14px;
}

.video-sidebar {
  width: 320px;
  flex-shrink: 0;
}

.related-videos {
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 12px;
  padding: var(--space-lg);
}

.related-videos h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-md);
}

.related-video-item {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.related-video-item:last-child {
  margin-bottom: 0;
}

.related-video-item .thumbnail {
  width: 100px;
  height: 60px;
  border-radius: 6px;
  overflow: hidden;
  flex-shrink: 0;
}

.related-video-item .thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.related-video-item .info {
  flex: 1;
  min-width: 0;
}

.related-video-item .info h4 {
  font-size: 13px;
  font-weight: 500;
  color: var(--tech-text);
  margin-bottom: 4px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: color var(--transition-normal);
}

.related-video-item:hover .info h4 {
  color: var(--tech-accent);
}

.related-video-item .info p {
  font-size: 12px;
  color: var(--tech-dim);
  margin-bottom: 2px;
}

/* ========================================
   辅助信息区
   ======================================== */

.aux-section {
  padding: var(--space-xl) 0;
  background: rgba(17, 34, 64, 0.4);
  border-top: 1px solid var(--tech-border);
  border-bottom: 1px solid var(--tech-border);
}

.aux-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}

.aux-card h3 {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-lg);
}

.aux-card h3 svg {
  width: 20px;
  height: 20px;
  color: var(--tech-accent);
}

.hot-list li {
  margin-bottom: var(--space-sm);
}

.hot-list a {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.hot-list .rank {
  width: 24px;
  height: 24px;
  border-radius: 4px;
  background: rgba(100, 255, 218, 0.1);
  color: var(--tech-accent);
  font-size: 12px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.hot-list .title {
  flex: 1;
  font-size: 14px;
  color: var(--tech-muted);
  transition: color var(--transition-normal);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.hot-list a:hover .title {
  color: var(--tech-accent);
}

.hot-list .icon {
  width: 14px;
  height: 14px;
  color: var(--tech-dim);
  flex-shrink: 0;
}

.update-list li {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.update-list .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--tech-accent);
  margin-top: 6px;
  flex-shrink: 0;
}

.update-list .content {
  flex: 1;
}

.update-list .content p {
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: 4px;
}

.update-list .content .date {
  font-size: 12px;
  color: var(--tech-dim);
}

.community-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.community-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md);
  background: var(--tech-card);
  border: 1px solid var(--tech-border);
  border-radius: 8px;
  transition: all var(--transition-normal);
}

.community-link:hover {
  border-color: var(--tech-accent);
}

.community-link .info p {
  font-size: 14px;
  font-weight: 500;
  color: var(--tech-text);
  margin-bottom: 2px;
}

.community-link .info span {
  font-size: 12px;
  color: var(--tech-muted);
}

.community-link svg {
  width: 18px;
  height: 18px;
  color: var(--tech-muted);
  transition: color var(--transition-normal);
}

.community-link:hover svg {
  color: var(--tech-accent);
}

/* ========================================
   底部
   ======================================== */

.footer {
  background: var(--tech-dark);
  border-top: 1px solid var(--tech-border);
  padding: var(--space-xl) 0 var(--space-lg);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.footer-brand img {
  height: 40px;
  margin-bottom: var(--space-md);
}

.footer-brand p {
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: var(--space-md);
  max-width: 280px;
}

.footer-brand .contact {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 14px;
  color: var(--tech-muted);
}

.footer-brand .contact svg {
  width: 16px;
  height: 16px;
}

.footer-links h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--tech-text);
  margin-bottom: var(--space-md);
}

.footer-links ul li {
  margin-bottom: var(--space-sm);
}

.footer-links a {
  font-size: 14px;
  color: var(--tech-muted);
  transition: color var(--transition-normal);
}

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

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--tech-border);
}

.footer-bottom p {
  font-size: 13px;
  color: var(--tech-dim);
}

.footer-bottom .legal-links {
  display: flex;
  gap: var(--space-lg);
}

.footer-bottom .legal-links a {
  font-size: 13px;
  color: var(--tech-dim);
  transition: color var(--transition-normal);
}

.footer-bottom .legal-links a:hover {
  color: var(--tech-accent);
}

/* ========================================
   栏目页头部 - 带分类介绍
   ======================================== */

.category-header {
  padding: var(--space-xl) 0 var(--space-lg);
  background: linear-gradient(180deg, rgba(17, 34, 64, 0.6) 0%, var(--tech-dark) 100%);
}

.category-header .back-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 14px;
  color: var(--tech-muted);
  margin-bottom: var(--space-md);
  transition: color var(--transition-normal);
}

.category-header .back-link:hover {
  color: var(--tech-accent);
}

.category-header h1 {
  font-size: 32px;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--space-sm);
}

.category-header p {
  color: var(--tech-muted);
  font-size: 15px;
  max-width: 600px;
}

/* ========================================
   移动端适配
   ======================================== */

@media (max-width: 1024px) {
  .section-cards-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .docs-grid,
  .videos-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .aux-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .content-with-sidebar,
  .doc-detail-layout {
    flex-direction: column;
  }
  
  .sidebar,
  .doc-detail-sidebar {
    width: 100%;
  }
  
  .sidebar-sticky {
    position: static;
  }
  
  .video-content-layout {
    flex-direction: column;
  }
  
  .video-sidebar {
    width: 100%;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 60px;
  }
  
  .navbar-menu,
  .navbar-search,
  .navbar-login {
    display: none;
  }
  
  .navbar-toggle {
    display: block;
  }
  
  .hero-carousel {
    height: 400px;
  }
  
  .carousel-slide h1 {
    font-size: 28px;
  }
  
  .carousel-slide p {
    font-size: 16px;
  }
  
  .carousel-nav {
    display: none;
  }
  
  .section-cards-grid,
  .docs-grid,
  .videos-grid,
  .aux-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-md);
    text-align: center;
  }
  
  .page-header h1 {
    font-size: 28px;
  }
  
  .video-info-header {
    flex-direction: column;
  }
  
  .video-actions {
    width: 100%;
  }
  
  .doc-content {
    padding: var(--space-lg);
  }
  
  .api-item-header {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
  }
  
  .api-item-header .right {
    width: 100%;
    justify-content: space-between;
  }
  
  .faq-item-header .meta {
    display: none;
  }
}

/* ========================================
   动画
   ======================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease forwards;
}

@keyframes glow {
  0%, 100% {
    box-shadow: 0 0 5px rgba(100, 255, 218, 0.2);
  }
  50% {
    box-shadow: 0 0 20px rgba(100, 255, 218, 0.4);
  }
}

.glow-animation {
  animation: glow 2s ease-in-out infinite;
}