/* ==========================================================
   上线性能与顺滑度增强引擎 (Smoothness & Performance Optimization)
   ========================================================== */
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  width: 100%;
}

*, *::before, *::after {
  box-sizing: border-box;
}

/* 硬件加速与流畅悬停 */
a, button, .media-news-card, .btn-media-primary, .btn-media-secondary, .faq-card, .intro-panel {
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  transform: translateZ(0);
}

/* 移动端平滑滚动与防抖 */
.table-wrapper, .table-container, .code-box, pre {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

/* 媒体图片防溢出与自适应 */
img, svg, video, canvas {
  max-width: 100%;
  height: auto;
  display: block;
}

/* 消除点击高亮延迟 */
a, button, input, select, textarea {
  -webkit-tap-highlight-color: transparent;
}

:root {
  /* 蓝白文档站风设计系统变量 (Blue & White Tech Docs Aesthetic) */
  --doc-bg: #f8fafc;              /* 文档站浅蓝灰底色 */
  --doc-bg-subtle: #f1f5f9;       /* 侧边栏/微底灰蓝 */
  --doc-surface: #ffffff;         /* 纯白卡片与正文背景 */
  --doc-primary: #2563eb;         /* 经典文档蓝 (Main Doc Blue) */
  --doc-primary-hover: #1d4ed8;   /* 深文档蓝 */
  --doc-primary-light: #eff6ff;   /* 极浅蓝背景 */
  --doc-primary-border: #bfdbfe;  /* 浅蓝边框 */
  --doc-secondary: #0ea5e9;       /* 辅助天蓝 */
  --doc-secondary-light: #f0f9ff; /* 浅天蓝微底 */
  
  --doc-text-main: #0f172a;       /* 浓郁深蓝黑主文字 */
  --doc-text-muted: #334155;      /* 严谨正文灰 */
  --doc-text-sub: #64748b;        /* 辅助说明灰 */
  
  --doc-border: #e2e8f0;          /* 经典文档边框色 */
  --doc-border-focus: #3b82f6;    /* 聚焦高亮蓝 */
  
  --doc-radius: 6px;              /* 文档规范圆角 */
  --doc-radius-lg: 10px;          /* 卡片与容器大圆角 */
  --doc-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px -1px rgba(0, 0, 0, 0.05);
  --doc-shadow-hover: 0 10px 15px -3px rgba(37, 99, 235, 0.08), 0 4px 6px -4px rgba(37, 99, 235, 0.05);
  --doc-transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --doc-font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --doc-font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--doc-font);
  background-color: var(--doc-bg);
  color: var(--doc-text-main);
  line-height: 1.7;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶部声明区 */
.doc-topbar {
  background-color: var(--doc-primary-light);
  border-bottom: 1px solid var(--doc-primary-border);
  padding: 10px 0;
  font-size: 13px;
  color: #1e40af;
}

.topbar-inner {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.doc-badge {
  display: inline-block;
  white-space: nowrap;
  background: var(--doc-primary);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.5px;
  margin-top: 1px;
}

.topbar-text {
  flex: 1;
  line-height: 1.55;
}

/* 文档站顶部导航 */
.doc-header {
  background: var(--doc-surface);
  border-bottom: 1px solid var(--doc-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 2px rgba(0,0,0,0.03);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 16px;
}

.doc-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.doc-logo-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--doc-radius);
  background: var(--doc-primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

.doc-title-group {
  display: flex;
  flex-direction: column;
}

.doc-main-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--doc-text-main);
  letter-spacing: -0.3px;
}

.doc-main-title span {
  color: var(--doc-primary);
}

.doc-sub-title {
  font-size: 11px;
  color: var(--doc-text-sub);
}

.doc-search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--doc-bg-subtle);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius);
  padding: 7px 14px;
  font-size: 13px;
  color: var(--doc-text-sub);
  width: 320px;
  cursor: pointer;
  transition: var(--doc-transition);
}

.doc-search-box:hover {
  border-color: var(--doc-primary);
  background: var(--doc-surface);
}

.doc-search-box kbd {
  margin-left: auto;
  font-size: 11px;
  background: #ffffff;
  border: 1px solid var(--doc-border);
  padding: 1px 6px;
  border-radius: 4px;
  font-family: var(--doc-font-mono);
}

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

.nav a {
  padding: 6px 12px;
  font-size: 14px;
  font-weight: 600;
  color: var(--doc-text-muted);
  text-decoration: none;
  border-radius: var(--doc-radius);
  transition: var(--doc-transition);
}

.nav a:hover {
  color: var(--doc-primary);
  background-color: var(--doc-primary-light);
}

.nav a.active {
  color: var(--doc-primary);
  background-color: var(--doc-primary-light);
  font-weight: 700;
}

/* 主标题区 / 英雄区 */
.doc-hero {
  padding: 56px 0 44px;
  text-align: center;
  background: linear-gradient(180deg, #ffffff 0%, var(--doc-bg) 100%);
  border-bottom: 1px solid var(--doc-border);
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 16px;
  background-color: var(--doc-primary-light);
  border: 1px solid var(--doc-primary-border);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 700;
  color: var(--doc-primary);
  margin-bottom: 20px;
}

.hero-pill .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--doc-primary);
}

.doc-hero h1 {
  font-size: 34px;
  font-weight: 900;
  color: var(--doc-text-main);
  line-height: 1.35;
  margin-bottom: 18px;
  letter-spacing: -0.5px;
}

.doc-hero p.hero-desc {
  max-width: 840px;
  margin: 0 auto 32px;
  font-size: 16px;
  color: var(--doc-text-muted);
  line-height: 1.8;
}

/* 双入口按钮 CTA */
.hero-cta-group {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.doc-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--doc-radius);
  text-decoration: none;
  transition: var(--doc-transition);
  cursor: pointer;
}

.btn-primary {
  background-color: var(--doc-primary);
  color: #ffffff;
  border: 1px solid var(--doc-primary-hover);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background-color: var(--doc-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
}

.btn-secondary {
  background-color: var(--doc-surface);
  color: var(--doc-text-main);
  border: 1px solid var(--doc-border);
  box-shadow: var(--doc-shadow);
}

.btn-secondary:hover {
  background-color: var(--doc-primary-light);
  border-color: var(--doc-primary-border);
  color: var(--doc-primary);
  transform: translateY(-2px);
}

/* 文档核心指标条 */
.doc-metric-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 980px;
  margin: 0 auto;
  padding: 16px 20px;
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius);
  box-shadow: var(--doc-shadow);
}

.metric-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  border-right: 1px solid var(--doc-border);
}

.metric-item:last-child {
  border-right: none;
}

.metric-item .val {
  font-size: 18px;
  font-weight: 800;
  color: var(--doc-primary);
}

.metric-item .lbl {
  font-size: 12px;
  color: var(--doc-text-sub);
  margin-top: 2px;
}

/* 模块通用样式 */
.section {
  padding: 60px 0;
}

.section-alt {
  background-color: var(--doc-surface);
  border-top: 1px solid var(--doc-border);
  border-bottom: 1px solid var(--doc-border);
}

.section-head {
  text-align: center;
  margin-bottom: 40px;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 800;
  color: var(--doc-primary);
  background: var(--doc-primary-light);
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: 10px;
  letter-spacing: 0.5px;
}

.section-head h2 {
  font-size: 26px;
  font-weight: 800;
  color: var(--doc-text-main);
  margin-bottom: 10px;
}

.section-head p {
  font-size: 15px;
  color: var(--doc-text-muted);
  max-width: 700px;
  margin: 0 auto;
}

/* 六宫格功能模块区 */
.grid-6 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-card {
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius-lg);
  padding: 26px 22px;
  transition: var(--doc-transition);
  display: flex;
  flex-direction: column;
  box-shadow: var(--doc-shadow);
}

.grid-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--doc-shadow-hover);
  border-color: var(--doc-primary-border);
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.card-stamp {
  font-family: var(--doc-font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--doc-primary);
  background: var(--doc-primary-light);
  padding: 3px 8px;
  border-radius: 4px;
  border: 1px solid var(--doc-primary-border);
}

.card-tag {
  font-size: 12px;
  font-weight: 600;
  color: var(--doc-text-sub);
}

.grid-card h3 {
  font-size: 17px;
  font-weight: 800;
  color: var(--doc-text-main);
  margin-bottom: 10px;
}

.grid-card p {
  font-size: 14px;
  color: var(--doc-text-muted);
  line-height: 1.65;
  margin-bottom: 18px;
  flex: 1;
}

.card-footer-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 700;
  color: var(--doc-primary);
  text-decoration: none;
  transition: var(--doc-transition);
}

.card-footer-link:hover {
  color: var(--doc-primary-hover);
  text-decoration: underline;
}

/* 正文介绍区（教程中心 + 我们提供什么） */
.intro-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
}

.intro-box {
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius-lg);
  padding: 32px 28px;
  box-shadow: var(--doc-shadow);
}

.intro-box h3 {
  font-size: 19px;
  font-weight: 800;
  color: var(--doc-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.intro-box p {
  font-size: 14px;
  color: var(--doc-text-muted);
  line-height: 1.75;
  margin-bottom: 16px;
}

.doc-callout {
  background: var(--doc-bg-subtle);
  border-left: 4px solid var(--doc-primary);
  padding: 12px 16px;
  border-radius: 0 var(--doc-radius) var(--doc-radius) 0;
  font-size: 13px;
  color: var(--doc-text-muted);
  margin-bottom: 16px;
}

.intro-feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.intro-feature-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 14px;
  color: var(--doc-text-main);
}

.feature-bullet {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--doc-primary);
  margin-top: 8px;
  flex-shrink: 0;
}

/* 热门教程表格 */
.table-wrapper {
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius-lg);
  overflow: hidden;
  box-shadow: var(--doc-shadow);
}

.doc-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.doc-table th {
  background-color: var(--doc-bg-subtle);
  padding: 15px 20px;
  font-size: 13px;
  font-weight: 800;
  color: var(--doc-text-main);
  border-bottom: 1px solid var(--doc-border);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.doc-table td {
  padding: 15px 20px;
  font-size: 14px;
  color: var(--doc-text-muted);
  border-bottom: 1px solid var(--doc-border);
  vertical-align: middle;
}

.doc-table tr:last-child td {
  border-bottom: none;
}

.doc-table tr:hover td {
  background-color: var(--doc-primary-light);
}

.badge-target {
  display: inline-block;
  background: var(--doc-bg-subtle);
  color: var(--doc-text-main);
  font-size: 12px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 4px;
  border: 1px solid var(--doc-border);
}

.badge-difficulty {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
}

.diff-easy {
  background: #ecfdf5;
  color: #065f46;
  border: 1px solid #a7f3d0;
}

.diff-med {
  background: #fffbeb;
  color: #92400e;
  border: 1px solid #fde68a;
}

.diff-hard {
  background: #fef2f2;
  color: #991b1b;
  border: 1px solid #fecaca;
}

/* FAQ 常见问答 */
.faq-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.faq-card {
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius);
  padding: 22px 20px;
  box-shadow: var(--doc-shadow);
}

.faq-card h4 {
  font-size: 15px;
  font-weight: 800;
  color: var(--doc-text-main);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.faq-card h4 .q-mark {
  color: var(--doc-primary);
  font-family: var(--doc-font-mono);
  font-weight: 900;
}

.faq-card p {
  font-size: 14px;
  color: var(--doc-text-muted);
  line-height: 1.7;
}

/* 延伸阅读区 */
.extended-reading {
  margin-top: 40px;
  background: var(--doc-primary-light);
  border: 1px solid var(--doc-primary-border);
  border-radius: var(--doc-radius-lg);
  padding: 24px 28px;
}

.extended-reading h4 {
  font-size: 15px;
  font-weight: 800;
  color: #1e40af;
  margin-bottom: 12px;
}

.extended-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.extended-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #ffffff;
  border: 1px solid var(--doc-primary-border);
  padding: 6px 14px;
  border-radius: var(--doc-radius);
  font-size: 13px;
  font-weight: 600;
  color: var(--doc-primary);
  text-decoration: none;
  transition: var(--doc-transition);
}

.extended-links a:hover {
  background: var(--doc-primary);
  color: #ffffff;
  transform: translateY(-2px);
}

/* 页脚 */
.doc-footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 50px 0 30px;
  border-top: 1px solid #1e293b;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
  padding-bottom: 30px;
  border-bottom: 1px solid #1e293b;
}

.footer-brand {
  max-width: 540px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  color: #ffffff;
  font-size: 16px;
}

.doc-logo-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  background: var(--doc-primary);
  color: #fff;
  border-radius: 4px;
}

.footer-brand p {
  font-size: 13px;
  line-height: 1.7;
  color: #64748b;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 20px;
  max-width: 440px;
}

.footer-nav a {
  color: #cbd5e1;
  text-decoration: none;
  font-size: 14px;
  transition: var(--doc-transition);
}

.footer-nav a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 24px;
  text-align: center;
  font-size: 12px;
  color: #475569;
}

/* 子页面内容容器与排版 */
.subpage-hero {
  padding: 40px 0 32px;
  background: var(--doc-surface);
  border-bottom: 1px solid var(--doc-border);
}

.subpage-hero h1 {
  font-size: 26px;
  font-weight: 900;
  color: var(--doc-text-main);
  margin-bottom: 10px;
  letter-spacing: -0.3px;
}

.subpage-hero p {
  font-size: 15px;
  color: var(--doc-text-muted);
}

.article-container {
  padding: 44px 0;
}

.article-content {
  background: var(--doc-surface);
  border: 1px solid var(--doc-border);
  border-radius: var(--doc-radius-lg);
  padding: 40px;
  box-shadow: var(--doc-shadow);
}

.article-content h2 {
  font-size: 20px;
  font-weight: 800;
  color: var(--doc-text-main);
  margin: 32px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--doc-border);
}

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

.article-content h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--doc-primary);
  margin: 24px 0 12px;
}

.article-content p {
  font-size: 15px;
  color: var(--doc-text-muted);
  line-height: 1.8;
  margin-bottom: 16px;
}

.article-content ul, .article-content ol {
  margin: 0 0 20px 24px;
  color: var(--doc-text-muted);
}

.article-content li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.doc-info-callout {
  background: var(--doc-primary-light);
  border-left: 4px solid var(--doc-primary);
  padding: 16px 20px;
  border-radius: 0 var(--doc-radius) var(--doc-radius) 0;
  margin-bottom: 24px;
  font-size: 14px;
  color: #1e40af;
}

.code-box {
  background: #0f172a;
  color: #f8fafc;
  padding: 18px 22px;
  border-radius: var(--doc-radius);
  font-family: var(--doc-font-mono);
  font-size: 13px;
  overflow-x: auto;
  margin-bottom: 20px;
  line-height: 1.6;
}

@media (max-width: 900px) {
  .doc-search-box {
    display: none;
  }
  .grid-6 {
    grid-template-columns: repeat(2, 1fr);
  }
  .intro-container {
    grid-template-columns: 1fr;
  }
  .faq-grid {
    grid-template-columns: 1fr;
  }
  .doc-metric-bar {
    grid-template-columns: repeat(2, 1fr);
  }
  .metric-item:nth-child(2) {
    border-right: none;
  }
}

@media (max-width: 640px) {
  .grid-6 {
    grid-template-columns: 1fr;
  }
  .header-inner {
    flex-direction: column;
    height: auto;
    padding: 14px 0;
    gap: 12px;
  }
  .doc-hero h1 {
    font-size: 24px;
  }
  .footer-top {
    flex-direction: column;
  }
  .doc-metric-bar {
    grid-template-columns: 1fr;
  }
  .metric-item {
    border-right: none;
    border-bottom: 1px solid var(--doc-border);
  }
  .metric-item:last-child {
    border-bottom: none;
  }
}