/* ==========================================================
   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 {
  /* 中文本地化风设计系统变量 (Chinese Localization Modern Aesthetic) */
  --cn-bg: #fdfbf7;              /* 典雅暖玉宣纸底色 */
  --cn-bg-subtle: #f5efe6;       /* 柔和米黄浅灰微底 */
  --cn-surface: #ffffff;         /* 纯白卡片背景 */
  --cn-primary: #8b1e1e;         /* 典雅朱砂绛红（主强调色） */
  --cn-primary-dark: #661212;    /* 浓郁深红 */
  --cn-primary-light: #fbeeed;   /* 极浅朱砂红微底 */
  --cn-secondary: #1a365d;       /* 沉稳青黛黛蓝（辅助强调） */
  --cn-secondary-light: #ebf3fa; /* 浅黛蓝微底 */
  --cn-accent: #c28e46;          /* 暖金泥/古雅金 */
  --cn-accent-light: #fdf6ec;    /* 极浅金色背景 */
  
  --cn-text-main: #1c1917;       /* 浓郁水墨主文字 */
  --cn-text-muted: #57534e;      /* 沉稳灰次要文字 */
  --cn-text-sub: #78716c;        /* 辅助说明灰 */
  
  --cn-border: #e7dfd5;          /* 宣纸淡雅边框 */
  --cn-border-focus: #8b1e1e;    /* 聚焦朱红边框 */
  
  --cn-radius: 8px;              /* 典雅微圆角 */
  --cn-radius-lg: 12px;          /* 模块容器大圆角 */
  --cn-shadow: 0 4px 16px rgba(28, 25, 23, 0.05);
  --cn-shadow-hover: 0 8px 24px rgba(139, 30, 30, 0.12);
  --cn-transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --cn-font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "HarmonyOS Sans SC", sans-serif;
}

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

body {
  font-family: var(--cn-font);
  background-color: var(--cn-bg);
  color: var(--cn-text-main);
  line-height: 1.75;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶部声明区 */
.cn-topbar {
  background-color: var(--cn-primary-light);
  border-bottom: 1px solid rgba(139, 30, 30, 0.15);
  padding: 10px 0;
  font-size: 13px;
  color: var(--cn-primary-dark);
}

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

.cn-badge {
  display: inline-block;
  white-space: nowrap;
  background: var(--cn-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;
}

/* 头部导航 */
.cn-header {
  background: var(--cn-surface);
  border-bottom: 1px solid var(--cn-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.02);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.cn-logo {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  color: inherit;
}

.cn-logo-icon {
  width: 40px;
  height: 40px;
  border-radius: 6px;
  background: var(--cn-primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 900;
  box-shadow: 0 2px 6px rgba(139, 30, 30, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

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

.cn-main-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--cn-text-main);
  letter-spacing: -0.2px;
}

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

.cn-sub-title {
  font-size: 11px;
  color: var(--cn-text-sub);
  letter-spacing: 0.2px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

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

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

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

/* 英雄区 / 主标题区 */
.cn-hero {
  padding: 56px 0 44px;
  text-align: center;
  background: radial-gradient(circle at center 20%, rgba(139, 30, 30, 0.04) 0%, transparent 70%);
  border-bottom: 1px solid var(--cn-border);
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 16px;
  background-color: var(--cn-primary-light);
  border: 1px solid rgba(139, 30, 30, 0.2);
  border-radius: 30px;
  font-size: 13px;
  font-weight: 700;
  color: var(--cn-primary);
  margin-bottom: 20px;
}

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

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

.cn-hero p.hero-desc {
  max-width: 820px;
  margin: 0 auto 32px;
  font-size: 16px;
  color: var(--cn-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;
}

.cn-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 28px;
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--cn-radius);
  text-decoration: none;
  transition: var(--cn-transition);
  cursor: pointer;
}

.btn-primary {
  background-color: var(--cn-primary);
  color: #ffffff;
  border: 1px solid var(--cn-primary-dark);
  box-shadow: 0 4px 12px rgba(139, 30, 30, 0.25);
}

.btn-primary:hover {
  background-color: var(--cn-primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(139, 30, 30, 0.35);
}

.btn-secondary {
  background-color: var(--cn-surface);
  color: var(--cn-secondary);
  border: 1px solid var(--cn-secondary);
}

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

/* 本地化关键指标条 */
.cn-metric-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 960px;
  margin: 0 auto;
  padding: 16px 20px;
  background: var(--cn-surface);
  border: 1px solid var(--cn-border);
  border-radius: var(--cn-radius);
  box-shadow: var(--cn-shadow);
}

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

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

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

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

/* 六宫格功能模块区 */
.section {
  padding: 60px 0;
}

.section-alt {
  background-color: var(--cn-bg-subtle);
  border-top: 1px solid var(--cn-border);
  border-bottom: 1px solid var(--cn-border);
}

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

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 800;
  color: var(--cn-primary);
  background: var(--cn-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(--cn-text-main);
  margin-bottom: 10px;
}

.section-head p {
  font-size: 15px;
  color: var(--cn-text-muted);
  max-width: 680px;
  margin: 0 auto;
}

.grid-6 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-card {
  background: var(--cn-surface);
  border: 1px solid var(--cn-border);
  border-radius: var(--cn-radius-lg);
  padding: 28px 24px;
  transition: var(--cn-transition);
  display: flex;
  flex-direction: column;
  position: relative;
}

.grid-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--cn-shadow-hover);
  border-color: rgba(139, 30, 30, 0.3);
}

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

.card-stamp {
  width: 38px;
  height: 38px;
  border-radius: 6px;
  background: var(--cn-primary-light);
  color: var(--cn-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 900;
  border: 1px solid rgba(139, 30, 30, 0.2);
}

.card-tag {
  font-size: 12px;
  font-weight: 600;
  color: var(--cn-secondary);
  background: var(--cn-secondary-light);
  padding: 2px 8px;
  border-radius: 4px;
}

.grid-card h3 {
  font-size: 18px;
  font-weight: 800;
  color: var(--cn-text-main);
  margin-bottom: 10px;
}

.grid-card p {
  font-size: 14px;
  color: var(--cn-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(--cn-primary);
  text-decoration: none;
  transition: var(--cn-transition);
}

.card-footer-link:hover {
  color: var(--cn-primary-dark);
  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: 32px;
}

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

.intro-box h3 {
  font-size: 20px;
  font-weight: 800;
  color: var(--cn-primary-dark);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.intro-box p {
  font-size: 14px;
  color: var(--cn-text-muted);
  line-height: 1.75;
  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(--cn-text-main);
}

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

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

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

.cn-table th {
  background-color: var(--cn-bg-subtle);
  padding: 16px 20px;
  font-size: 14px;
  font-weight: 800;
  color: var(--cn-text-main);
  border-bottom: 1px solid var(--cn-border);
}

.cn-table td {
  padding: 16px 20px;
  font-size: 14px;
  color: var(--cn-text-muted);
  border-bottom: 1px solid var(--cn-border);
  vertical-align: middle;
}

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

.cn-table tr:hover td {
  background-color: rgba(139, 30, 30, 0.02);
}

.badge-target {
  display: inline-block;
  background: var(--cn-secondary-light);
  color: var(--cn-secondary);
  font-size: 12px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
}

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

.diff-easy {
  background: #ecfdf5;
  color: #065f46;
}

.diff-med {
  background: #fffbeb;
  color: #92400e;
}

.diff-hard {
  background: #fef2f2;
  color: #991b1b;
}

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

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

.faq-card h4 {
  font-size: 16px;
  font-weight: 800;
  color: var(--cn-text-main);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}

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

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

/* 延伸阅读区 */
.extended-reading {
  margin-top: 40px;
  background: var(--cn-accent-light);
  border: 1px solid rgba(194, 142, 70, 0.3);
  border-radius: var(--cn-radius-lg);
  padding: 24px 28px;
}

.extended-reading h4 {
  font-size: 16px;
  font-weight: 800;
  color: #78350f;
  margin-bottom: 12px;
}

.extended-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.extended-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #ffffff;
  border: 1px solid rgba(194, 142, 70, 0.3);
  padding: 6px 14px;
  border-radius: var(--cn-radius);
  font-size: 13px;
  font-weight: 600;
  color: #92400e;
  text-decoration: none;
  transition: var(--cn-transition);
}

.extended-links a:hover {
  border-color: var(--cn-primary);
  color: var(--cn-primary);
  transform: translateY(-2px);
}

/* 页脚 */
.cn-footer {
  background: #1c1917;
  color: #a8a29e;
  padding: 50px 0 30px;
  border-top: 3px solid var(--cn-primary);
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
  padding-bottom: 30px;
  border-bottom: 1px solid #292524;
}

.footer-brand {
  max-width: 520px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  color: #ffffff;
  font-size: 17px;
}

.cn-logo-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  background: var(--cn-primary);
  color: #fff;
  border-radius: 4px;
  font-size: 14px;
  font-weight: 900;
}

.footer-brand p {
  font-size: 13px;
  line-height: 1.7;
  color: #78716c;
}

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

.footer-nav a {
  color: #d6d3d1;
  text-decoration: none;
  font-size: 14px;
  transition: var(--cn-transition);
}

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

.footer-bottom {
  padding-top: 24px;
  text-align: center;
  font-size: 12px;
  color: #57534e;
}

/* 子页面内容容器与排版 */
.subpage-hero {
  padding: 44px 0 36px;
  background: var(--cn-surface);
  border-bottom: 1px solid var(--cn-border);
}

.subpage-hero h1 {
  font-size: 28px;
  font-weight: 900;
  color: var(--cn-text-main);
  margin-bottom: 12px;
}

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

.article-container {
  padding: 48px 0;
}

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

.article-content h2 {
  font-size: 22px;
  font-weight: 800;
  color: var(--cn-primary-dark);
  margin: 32px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--cn-border);
}

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

.article-content h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--cn-text-main);
  margin: 24px 0 12px;
}

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

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

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

.info-banner {
  background: var(--cn-primary-light);
  border-left: 4px solid var(--cn-primary);
  padding: 16px 20px;
  border-radius: 0 var(--cn-radius) var(--cn-radius) 0;
  margin-bottom: 24px;
  font-size: 14px;
  color: var(--cn-primary-dark);
}

.code-block {
  background: #1c1917;
  color: #f5f5f4;
  padding: 16px 20px;
  border-radius: var(--cn-radius);
  font-family: "Courier New", Courier, monospace;
  font-size: 13px;
  overflow-x: auto;
  margin-bottom: 20px;
  line-height: 1.6;
}

@media (max-width: 900px) {
  .grid-6 {
    grid-template-columns: repeat(2, 1fr);
  }
  .intro-container {
    grid-template-columns: 1fr;
  }
  .faq-grid {
    grid-template-columns: 1fr;
  }
  .cn-metric-bar {
    grid-template-columns: repeat(2, 1fr);
  }
  .metric-item:nth-child(2) {
    border-right: none;
  }
  .metric-item {
    padding: 8px 0;
  }
}

@media (max-width: 640px) {
  .grid-6 {
    grid-template-columns: 1fr;
  }
  .header-inner {
    flex-direction: column;
    height: auto;
    padding: 16px 0;
    gap: 12px;
  }
  .cn-hero h1 {
    font-size: 24px;
  }
  .footer-top {
    flex-direction: column;
  }
  .cn-metric-bar {
    grid-template-columns: 1fr;
  }
  .metric-item {
    border-right: none;
    border-bottom: 1px solid var(--cn-border);
  }
  .metric-item:last-child {
    border-bottom: none;
  }
}