/* ===================================================================
   厚道云 (HouDaoYun) - 工业极简设计风格样式表
   规范：冷灰色调、精细线框、工程等宽编码、高对比度、清晰层级、移动端优先
   =================================================================== */

:root {
  /* 基础色板：冷灰与工业深色 */
  --bg-primary: #0b0d10;
  --bg-secondary: #12151b;
  --bg-card: #161922;
  --bg-card-hover: #1c212c;
  --bg-surface: #1f2430;
  
  /* 线框与边框 */
  --border-light: #242a38;
  --border-medium: #313849;
  --border-accent: #3b82f6;
  --border-active: #00e5a3;

  /* 文字颜色 */
  --text-primary: #f1f3f7;
  --text-secondary: #9da6b8;
  --text-muted: #646e82;
  --text-link: #60a5fa;

  /* 状态指示色 */
  --status-online: #00e5a3;
  --status-warning: #f59e0b;
  --status-accent: #3b82f6;

  /* 字体族系 */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Consolas, "Roboto Mono", Menlo, monospace;

  /* 几何尺寸与圆角 */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;
  --max-width: 1200px;
  --header-height: 72px;

  /* 阴影与过渡 */
  --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-card: 0 8px 30px rgba(0, 0, 0, 0.5);
  --transition-fast: 0.18s ease;
  --transition-normal: 0.25s ease;
}

/* 基础重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.65;
  background-image: 
    linear-gradient(rgba(36, 42, 56, 0.25) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 42, 56, 0.25) 1px, transparent 1px);
  background-size: 48px 48px;
  background-position: -1px -1px;
  min-height: 100vh;
  overflow-x: hidden;
}

/* 尊重减少动态设置 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

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

img, svg {
  vertical-align: middle;
  max-width: 100%;
  height: auto;
}

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

/* 工业编号与徽章通用样式 */
.tech-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background-color: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #93c5fd;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.tech-tag.success {
  background-color: rgba(0, 229, 163, 0.1);
  border-color: rgba(0, 229, 163, 0.3);
  color: var(--status-online);
}

.pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--status-online);
  display: inline-block;
  box-shadow: 0 0 8px var(--status-online);
  animation: pulseAnim 2s infinite ease-in-out;
}

@keyframes pulseAnim {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

/* 容器与布局 */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0;
  border-bottom: 1px solid var(--border-light);
  position: relative;
}

.section-header {
  margin-bottom: 48px;
  text-align: left;
}

.section-num {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-link);
  margin-bottom: 8px;
  display: block;
  letter-spacing: 0.08em;
}

.section-title {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 680px;
  line-height: 1.7;
}

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  text-align: center;
  transition: all var(--transition-fast);
  white-space: nowrap;
  outline: none;
  min-height: 46px;
}

.btn:focus-visible {
  outline: 2px solid var(--border-accent);
  outline-offset: 3px;
}

.btn-primary {
  background-color: var(--border-accent);
  color: #ffffff;
  border: 1px solid #60a5fa;
  box-shadow: 0 2px 10px rgba(59, 130, 246, 0.35);
}

.btn-primary:hover {
  background-color: #2563eb;
  border-color: #93c5fd;
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0);
}

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

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

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-medium);
}

.btn-outline:hover {
  background-color: rgba(255, 255, 255, 0.05);
  border-color: var(--border-accent);
  color: var(--text-link);
}

/* 页眉 Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(11, 13, 16, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  height: var(--header-height);
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

.logo-icon {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #1e293b, #0f172a);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-sm);
  color: var(--status-online);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
  position: relative;
  padding: 6px 0;
}

.nav-link:hover, .nav-link:focus-visible {
  color: var(--text-primary);
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--border-accent);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.mobile-menu-btn {
  display: none;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
}

/* 主视觉 Hero */
.hero-section {
  padding: 70px 0 90px;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.hero-content {
  max-width: 620px;
}

.hero-badge-row {
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.hero-title {
  font-size: 2.75rem;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
  color: #ffffff;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #ffffff 40%, #94a3b8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border-light);
}

.stat-item {
  display: flex;
  flex-direction: column;
}

.stat-val {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* 桌面端 Hero 动态图卡 / 矩阵仪表盘 */
.hero-visual {
  position: relative;
}

.dashboard-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-card);
  position: relative;
}

.card-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 20px;
}

.terminal-dots {
  display: flex;
  gap: 6px;
}

.terminal-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--border-medium);
}

.terminal-dots span:nth-child(1) { background-color: #ef4444; }
.terminal-dots span:nth-child(2) { background-color: #f59e0b; }
.terminal-dots span:nth-child(3) { background-color: #10b981; }

.dashboard-title {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.node-matrix-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.node-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  transition: border-color var(--transition-fast);
}

.node-row:hover {
  border-color: var(--border-accent);
}

.node-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.node-flag {
  font-size: 1.1rem;
}

.node-name {
  font-weight: 600;
  color: var(--text-primary);
}

.node-protocol {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.node-metrics {
  display: flex;
  align-items: center;
  gap: 14px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.node-ping {
  color: var(--status-online);
}

.node-loss {
  color: var(--text-secondary);
}

/* 核心优势 Cards */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  position: relative;
}

.feature-card:hover {
  border-color: var(--border-medium);
  background-color: var(--bg-card-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-subtle);
}

.card-num {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-link);
  margin-bottom: 16px;
  display: block;
}

.feature-icon-box {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-medium);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--border-accent);
  margin-bottom: 18px;
}

.feature-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.925rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* 流媒体与 AI 支持 */
.support-wrapper {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 36px;
}

.support-subhead {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.support-items-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}

.support-box {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 18px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  transition: border-color var(--transition-fast);
}

.support-box:hover {
  border-color: var(--border-medium);
}

.support-icon {
  font-size: 1.5rem;
  line-height: 1;
}

.support-text h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.support-text p {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.support-notice-box {
  background-color: rgba(30, 41, 59, 0.4);
  border-left: 3px solid var(--border-accent);
  padding: 16px 20px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 套餐对比 Pricing */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  align-items: stretch;
}

.pricing-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all var(--transition-normal);
}

.pricing-card:hover {
  border-color: var(--border-medium);
  transform: translateY(-2px);
}

.pricing-card.featured {
  border-color: var(--border-accent);
  background-color: #171c26;
  box-shadow: 0 0 25px rgba(59, 130, 246, 0.15);
}

.card-ribbon {
  position: absolute;
  top: 14px;
  right: 14px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background: var(--border-accent);
  color: #fff;
  font-weight: 600;
}

.plan-header {
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-light);
}

.plan-code {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  display: block;
  margin-bottom: 4px;
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.plan-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-top: 12px;
}

.plan-currency {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.plan-amount {
  font-family: var(--font-mono);
  font-size: 2.2rem;
  font-weight: 800;
  color: #ffffff;
}

.plan-period {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.plan-traffic-badge {
  display: inline-block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--status-online);
}

.plan-features-list {
  list-style: none;
  margin-bottom: 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  flex-grow: 1;
}

.plan-features-list li {
  font-size: 0.875rem;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.plan-features-list li svg {
  flex-shrink: 0;
  margin-top: 3px;
  color: var(--status-online);
}

.plan-action {
  margin-top: auto;
}

.plan-action .btn {
  width: 100%;
}

/* 常见问题 FAQ */
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.faq-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
}

.faq-question {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.faq-q-tag {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--border-accent);
}

.faq-answer {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* 页脚 Footer */
.site-footer {
  background-color: #080a0d;
  border-top: 1px solid var(--border-light);
  padding: 60px 0 40px;
  margin-top: 40px;
}

.footer-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 40px;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--border-light);
  flex-wrap: wrap;
  gap: 32px;
}

.footer-brand {
  max-width: 360px;
}

.footer-brand-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.footer-brand-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.footer-links-only {
  display: flex;
  gap: 32px;
  flex-wrap: wrap;
}

.footer-link-item {
  font-size: 0.9rem;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.footer-link-item:hover, .footer-link-item:focus-visible {
  color: var(--border-accent);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 16px;
}

.footer-domain {
  font-family: var(--font-mono);
  color: var(--text-secondary);
}

/* 侧边章节箭头导航浮动组件 */
.chapter-nav-widget {
  position: fixed;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 90;
  background-color: rgba(18, 21, 27, 0.85);
  border: 1px solid var(--border-medium);
  border-radius: 30px;
  padding: 8px 6px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.chapter-arrow-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-light);
  transition: all var(--transition-fast);
}

.chapter-arrow-btn:hover:not(:disabled) {
  background-color: var(--border-accent);
  color: #ffffff;
  border-color: var(--border-accent);
}

.chapter-arrow-btn:disabled {
  opacity: 0.25;
  cursor: not-allowed;
  pointer-events: none;
}

.chapter-indicator {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-align: center;
  color: var(--text-muted);
  padding: 4px 0;
  user-select: none;
}

/* 文章列表与文章正文专用样式 */
.article-header {
  padding: 50px 0 30px;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 40px;
}

.breadcrumb-nav {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.breadcrumb-nav a {
  color: var(--text-secondary);
}

.breadcrumb-nav a:hover {
  color: var(--border-accent);
}

.breadcrumb-sep {
  color: var(--border-medium);
}

.article-main-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 16px;
  color: #ffffff;
}

.article-meta-row {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.article-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.article-container {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 48px;
  align-items: start;
}

.article-body {
  font-size: 1.05rem;
  line-height: 1.85;
  color: #d1d5db;
}

.article-body h2 {
  font-size: 1.55rem;
  font-weight: 700;
  color: #ffffff;
  margin: 40px 0 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-light);
}

.article-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: #f3f4f6;
  margin: 28px 0 12px;
}

.article-body p {
  margin-bottom: 20px;
}

.article-body ul, .article-body ol {
  margin: 0 0 24px 24px;
}

.article-body li {
  margin-bottom: 8px;
}

.article-body blockquote {
  border-left: 3px solid var(--border-accent);
  padding: 14px 20px;
  background-color: var(--bg-card);
  margin: 24px 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-secondary);
}

.article-body pre {
  background-color: #0f1217;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 16px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.5;
  margin: 24px 0;
  color: #e5e7eb;
}

.article-body code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background-color: var(--bg-surface);
  padding: 2px 6px;
  border-radius: 3px;
  color: #93c5fd;
}

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

.article-promo-box {
  background: linear-gradient(135deg, rgba(30, 41, 59, 0.6), rgba(15, 23, 42, 0.8));
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-md);
  padding: 28px;
  margin: 36px 0;
  text-align: center;
}

.article-promo-box h4 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: #ffffff;
}

.article-promo-box p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  max-width: 540px;
  margin: 0 auto 20px;
}

/* 侧边栏 */
.sidebar-sticky {
  position: sticky;
  top: 90px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sidebar-widget {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
}

.sidebar-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-primary);
}

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

.sidebar-article-list li a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.45;
  display: block;
  transition: color var(--transition-fast);
}

.sidebar-article-list li a:hover {
  color: var(--border-accent);
}

/* 文章列表页专用卡片 */
.articles-catalog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.article-card-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
}

.article-card-item:hover {
  border-color: var(--border-medium);
  background-color: var(--bg-card-hover);
  transform: translateY(-2px);
}

.article-card-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-link);
  margin-bottom: 10px;
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card-excerpt {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-muted);
  padding-top: 14px;
  border-top: 1px solid var(--border-light);
}

/* 网站地图与独立信息页样式 */
.info-card-content {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 36px;
  line-height: 1.8;
  color: #d1d5db;
}

.info-card-content h2 {
  font-size: 1.4rem;
  font-weight: 700;
  color: #fff;
  margin: 32px 0 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-light);
}

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

.info-card-content p {
  margin-bottom: 16px;
}

.sitemap-columns {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 24px;
}

.sitemap-group {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 20px;
}

.sitemap-group-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 8px;
}

.sitemap-group ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sitemap-group li a {
  font-size: 0.9rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 6px;
}

.sitemap-group li a:hover {
  color: var(--border-accent);
}

/* 响应式断点适配 */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .support-items-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-catalog-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-container {
    grid-template-columns: 1fr;
  }
  .sidebar-sticky {
    position: static;
  }
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }
  .hero-title {
    font-size: 2rem;
  }
  .section-title {
    font-size: 1.6rem;
  }
  .site-nav {
    display: none; /* 移动端抽屉或折叠 */
  }
  .site-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-medium);
    padding: 20px 24px;
    gap: 16px;
  }
  .mobile-menu-btn {
    display: flex;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .faq-grid {
    grid-template-columns: 1fr;
  }
  .support-items-grid {
    grid-template-columns: 1fr;
  }
  .articles-catalog-grid {
    grid-template-columns: 1fr;
  }
  .sitemap-columns {
    grid-template-columns: 1fr;
  }
  .hero-stats {
    grid-template-columns: 1fr;
    gap: 12px;
  }
  .chapter-nav-widget {
    right: 10px;
    padding: 6px 4px;
  }
  .chapter-arrow-btn {
    width: 32px;
    height: 32px;
  }
}