/* ==========================================================================
   山水云机场 - 第3套：长卷分幅系统 (Horizontal Band & Proportional Split System)
   现代编辑型暖白风 · 超宽横向内容幅 · 不等比信息分栏 · 连续纵向阅读
   ========================================================================== */

:root {
  /* 核心色彩系统 (#17) */
  --bg: #FBFAF7;
  --surface: #FFFFFF;
  --surface-alt: #F2F0EB;
  --text: #1F2527;
  --body: #5D6567;
  --muted: #899093;
  --blue: #455F69;
  --blue-dark: #354A53;
  --green: #607067;
  --green-dark: #4B5A52;
  --stone: #A27A59;
  --accent: #B06C50;
  --tint-blue: #EEF1F2;
  --tint-green: #EEF1EE;
  --tint-warm: #F5EEE7;
  --border: #E1DED8;
  --footer-text: #4C5557;

  /* 字体系统 (#21) */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;

  /* 尺寸与间距 */
  --container-max: 1360px;
  --header-height: 70px;
  --radius: 4px;
  --shadow-subtle: 0 10px 28px rgba(31, 37, 39, 0.02);
}

/* 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%;
  background-color: var(--bg);
  color: var(--text);
}

body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.8;
  color: var(--body);
  background-color: var(--bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--text);
  text-decoration: none;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

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

ul, ol {
  list-style: none;
}

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

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

/* 可访问性焦点样式 (#269) */
a:focus-visible,
button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
  border-radius: 2px;
}

/* 页面容器 */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 28px;
}

/* 标题与排版系统 (#21) */
h1, h2, h3, h4 {
  color: var(--text);
  font-weight: 600;
  letter-spacing: -0.015em;
  line-height: 1.32;
}

h1 {
  font-size: clamp(32px, 3.6vw, 48px);
}

h2 {
  font-size: clamp(24px, 2.5vw, 34px);
}

h3 {
  font-size: clamp(19px, 1.6vw, 23px);
}

p {
  margin-bottom: 1em;
}

p:last-child {
  margin-bottom: 0;
}

/* 编号与标签装饰 */
.band-index {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 600;
  color: var(--blue);
  letter-spacing: 0.04em;
  margin-bottom: 12px;
}

.band-index::before {
  content: "";
  display: inline-block;
  width: 22px;
  height: 1.5px;
  background-color: var(--stone);
}

.big-num {
  font-size: clamp(40px, 4.2vw, 60px);
  font-weight: 600;
  line-height: 1;
  color: var(--blue-dark);
  letter-spacing: -0.03em;
}

.tag-badge {
  display: inline-block;
  padding: 2px 9px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--blue-dark);
  background-color: var(--tint-blue);
  border: 1px solid var(--border);
  border-radius: 2px;
}

.tag-badge.terracotta {
  background-color: var(--accent);
  color: #FFFFFF;
  border-color: var(--accent);
}

.tag-badge.green {
  background-color: var(--tint-green);
  color: var(--green-dark);
}

.tag-badge.warm {
  background-color: var(--tint-warm);
  color: var(--stone);
}

/* ==========================================================================
   Header 顶部导航 (#26 - #29)
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background-color: var(--bg);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: 20px;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  flex-shrink: 0;
}

.brand-link:hover {
  color: var(--text);
}

.brand-logo {
  width: 58px;
  height: 28px;
  flex-shrink: 0;
}

.brand-text-group {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.01em;
}

.brand-sub {
  font-size: 11px;
  color: var(--muted);
  margin-top: 2px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.nav-link {
  position: relative;
  font-size: 14px;
  color: var(--body);
  padding: 6px 0;
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--text);
}

.nav-link.active {
  color: var(--text);
  font-weight: 600;
}

/* 当前项下方20px短线 (#28) */
.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 20px;
  height: 2px;
  background-color: var(--text);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
}

/* 按钮与链接样式 (#35, #238) */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 9px 18px;
  font-size: 14px;
  font-weight: 600;
  color: #FFFFFF;
  background-color: var(--blue-dark);
  border: 1px solid var(--blue-dark);
  border-radius: 3px;
  line-height: 1.4;
  white-space: nowrap;
}

.btn-primary:hover {
  background-color: var(--blue);
  border-color: var(--blue);
  color: #FFFFFF;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 9px 18px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 3px;
  line-height: 1.4;
  white-space: nowrap;
}

.btn-secondary:hover {
  border-color: var(--blue);
  color: var(--blue);
  background-color: var(--tint-blue);
}

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 14px;
  font-weight: 600;
  color: var(--blue-dark);
  border-bottom: 1px solid transparent;
}

.link-arrow:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.btn-primary .arrow,
.btn-secondary .arrow,
.link-arrow .arrow {
  display: inline-block;
  transition: transform 0.18s ease;
}

.btn-primary:hover .arrow,
.btn-secondary:hover .arrow,
.link-arrow:hover .arrow {
  transform: translateX(3px);
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
  display: none;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 3px;
  background-color: var(--surface);
}

.mobile-nav-drawer {
  display: none;
  background-color: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 16px 28px 24px;
}

.mobile-nav-drawer.is-open {
  display: block;
}

.mobile-nav-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px 20px;
  margin-bottom: 16px;
}

.mobile-nav-list a {
  display: block;
  padding: 8px 0;
  font-size: 15px;
  color: var(--text);
  border-bottom: 1px solid var(--surface-alt);
}

/* ==========================================================================
   长卷分幅核心结构 (Horizontal Band System #3 - #10, #19, #47 - #49)
   ========================================================================== */
.scroll-section {
  padding: 44px 0;
  border-bottom: 1px solid var(--border);
}

.scroll-section.bg-warm {
  background-color: var(--bg);
}

.scroll-section.bg-white {
  background-color: var(--surface);
}

.scroll-section.bg-alt {
  background-color: var(--surface-alt);
}

.scroll-section.bg-green-tint {
  background-color: var(--tint-green);
}

/* 每一幅顶部标题说明条 */
.section-head-bar {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 22px;
}

.section-head-main {
  max-width: 820px;
}

.section-head-main h2 {
  margin-bottom: 8px;
}

.section-lead {
  font-size: 16px;
  color: var(--body);
}

/* 统一横幅外框 (#5, #38, #39) */
.band-frame {
  width: 100%;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-subtle);
  overflow: hidden;
}

.scroll-section.bg-white .band-frame {
  background-color: var(--bg);
}

/* 横幅内部分区通用单元格 */
.band-pane {
  padding: 34px 32px;
  min-width: 0;
}

.band-pane + .band-pane {
  border-left: 1px solid var(--border);
}

.pane-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  padding-bottom: 12px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--border);
}

.pane-label strong {
  color: var(--text);
  font-size: 14px;
}

/* ==========================================================================
   第一幅：Hero (52% / 29% / 19% 不等比分幅 #30 - #45)
   ========================================================================== */
.hero-section {
  padding: 36px 0 48px;
  background-color: var(--bg);
  border-bottom: 1px solid var(--border);
}

.hero-frame {
  display: grid;
  grid-template-columns: 52fr 29fr 19fr;
  min-height: 600px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-subtle);
}

.hero-pane-main {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 44px 42px;
  background-color: var(--surface);
}

.hero-kicker {
  display: flex;
   flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}

.hero-kicker-brand {
  font-size: 14px;
  font-weight: 700;
  color: var(--blue-dark);
}

.hero-kicker-sep {
  color: var(--border);
}

.hero-kicker-sub {
  font-size: 13px;
  color: var(--muted);
}

.hero-editorial-slogan {
  font-size: clamp(22px, 2.2vw, 30px);
  font-weight: 600;
  color: var(--blue-dark);
  line-height: 1.4;
  margin-bottom: 16px;
  padding-left: 14px;
  border-left: 3px solid var(--stone);
}

.hero-pane-main h1 {
  font-size: clamp(30px, 3.1vw, 46px);
  line-height: 1.26;
  margin-bottom: 20px;
  color: var(--text);
}

.hero-desc {
  font-size: 17px;
  color: var(--body);
  line-height: 1.85;
  margin-bottom: 28px;
}

.hero-cta-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 20px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.hero-pane-mid {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 40px 30px;
  background-color: var(--bg);
  border-left: 1px solid var(--border);
}

.hero-sub-group + .hero-sub-group {
  margin-top: 26px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.hero-group-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hero-tier-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}

.hero-tier-item {
  padding: 10px 12px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 2px;
}

.hero-tier-item strong {
  display: block;
  font-size: 16px;
  color: var(--text);
}

.hero-tier-item span {
  font-size: 12px;
  color: var(--muted);
}

.hero-node-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px 12px;
}

.hero-node-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 10px;
  background-color: var(--surface);
  border-bottom: 1px solid var(--border);
  font-size: 14px;
  color: var(--text);
}

.hero-node-item em {
  font-style: normal;
  font-size: 12px;
  color: var(--muted);
}

.hero-pane-right {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 40px 24px;
  background-color: var(--surface-alt);
  border-left: 1px solid var(--border);
}

.hero-guide-list {
  display: flex;
  flex-direction: column;
}

.hero-guide-item {
  display: flex;
   flex-direction: column;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}

.hero-guide-item:first-child {
  padding-top: 0;
}

.hero-guide-item strong {
  font-size: 15px;
  color: var(--text);
  margin-bottom: 2px;
}

.hero-guide-item span {
  font-size: 12px;
  color: var(--body);
}

/* ==========================================================================
   第二幅：套餐分幅 (44% / 34% / 22% #50 - #61)
   ========================================================================== */
.grid-plans {
  display: grid;
  grid-template-columns: 44fr 34fr 22fr;
}

.plan-logic-list {
  margin-top: 18px;
  display: grid;
  gap: 10px;
}

.plan-logic-item {
  padding: 10px 14px;
  background-color: var(--bg);
  border-left: 2px solid var(--blue);
  font-size: 14px;
}

.plan-logic-item strong {
  color: var(--text);
  margin-right: 6px;
}

.tier-strip-list {
  display: flex;
  flex-direction: column;
  height: 100%;
  justify-content: space-between;
}

.tier-strip {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}

.tier-strip:first-child {
  padding-top: 0;
}

.tier-strip:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.tier-strip-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 4px;
}

.tier-strip-head strong {
  font-size: 17px;
  color: var(--text);
}

.tier-strip-head .tier-vol {
  font-size: 16px;
  font-weight: 700;
  color: var(--blue-dark);
}

.tier-strip p {
  font-size: 14px;
  color: var(--body);
}

.plan-side-box {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background-color: var(--tint-warm);
}

.longterm-highlight {
  padding: 18px 16px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  margin: 16px 0;
}

.longterm-highlight .lt-vol {
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.2;
}

.longterm-highlight .lt-price {
  font-size: 20px;
  font-weight: 600;
  color: var(--stone);
  margin: 4px 0 8px;
}

/* ==========================================================================
   第三幅：节点地区分幅 (34% / 26% / 40% #62 - #73)
   ========================================================================== */
.grid-nodes {
  display: grid;
  grid-template-columns: 34fr 26fr 40fr;
}

.node-stack {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 24px;
}

.node-stack-item + .node-stack-item {
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.node-title-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.node-title-row h3 {
  font-size: 21px;
}

.node-meta-list {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--border);
  font-size: 14px;
  color: var(--body);
}

.node-guide-callout {
  margin-top: 20px;
  padding: 16px 18px;
  background-color: var(--tint-blue);
  border-left: 3px solid var(--blue);
}

/* ==========================================================================
   第四幅：线路知识分幅 (60% / 40% + 底部比较表 #74 - #87)
   ========================================================================== */
.grid-lines {
  display: grid;
  grid-template-columns: 60fr 40fr;
}

.line-qa-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 20px;
}

.line-qa-item {
  padding: 14px 16px;
  background-color: var(--bg);
  border: 1px solid var(--border);
}

.line-qa-item h4 {
  font-size: 15px;
  margin-bottom: 6px;
  color: var(--text);
}

.line-qa-item p {
  font-size: 14px;
  line-height: 1.65;
}

.line-Quick-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.line-quick-row {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
}

.line-quick-row:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.line-quick-row h3 {
  font-size: 18px;
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.line-quick-row p {
  font-size: 14px;
}

/* 线路横向细线表格 (#83 - #85) */
.band-table-wrap {
  border-top: 1px solid var(--border);
  padding: 26px 32px 30px;
  background-color: var(--surface);
}

.table-caption-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.editorial-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 15px;
}

.editorial-table th {
  padding: 12px 16px 12px 0;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  border-bottom: 1.5px solid var(--text);
}

.editorial-table td {
  padding: 14px 16px 14px 0;
  color: var(--body);
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

.editorial-table td:first-child {
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
}

/* ==========================================================================
   第五幅：AI与流媒体分幅 (57% / 43% #88 - #99)
   ========================================================================== */
.grid-ai-stream {
  display: grid;
  grid-template-columns: 57fr 43fr;
}

.platform-primary-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 18px 0;
}

.platform-row {
  padding: 14px 16px;
  background-color: var(--surface);
  border: 1px solid var(--border);
}

.scroll-section.bg-warm .platform-row {
  background-color: var(--bg);
}

.platform-row-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.platform-row-head h3 {
  font-size: 18px;
}

.platform-factors {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  font-size: 13px;
}

.factor-cell {
  padding-top: 6px;
  border-top: 1px solid var(--border);
}

.factor-cell strong {
  display: block;
  color: var(--text);
  margin-bottom: 2px;
}

.compact-platform-strip {
  padding-top: 14px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 14px;
}

.compact-platform-line {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.compact-platform-line strong {
  min-width: 125px;
  color: var(--text);
  flex-shrink: 0;
}

/* ==========================================================================
   第六幅：客户端分幅 (36% / 64% #100 - #110)
   ========================================================================== */
.grid-clients {
  display: grid;
  grid-template-columns: 36fr 64fr;
}

.device-check-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin: 18px 0;
}

.device-item {
  padding: 12px 14px;
  background-color: var(--surface);
  border: 1px solid var(--border);
}

.device-item strong {
  display: block;
  font-size: 16px;
  color: var(--text);
}

.device-item span {
  font-size: 12px;
  color: var(--muted);
}

.client-sub-groups {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.client-group-block {
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}

.client-group-block:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.client-group-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--blue-dark);
  margin-bottom: 12px;
  text-transform: uppercase;
}

.os-dual-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.os-detail-box h3 {
  font-size: 18px;
  margin-bottom: 6px;
}

.os-detail-box p {
  font-size: 14px;
}

.step-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.step-tags span {
  font-size: 12px;
  padding: 2px 8px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
}

/* ==========================================================================
   第七幅：完整价格“主幅 + 四条辅助幅” (40% / 60% #111 - #126)
   ========================================================================== */
.pricing-frame {
  display: grid;
  grid-template-columns: 40fr 60fr;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

/* 左侧主力方案 (#114, #122) */
.pricing-main-band {
  padding: 40px 36px;
  background-color: var(--tint-green);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.pricing-main-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.pricing-main-title {
  font-size: 26px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 6px;
}

.pricing-main-vol {
  font-size: 20px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 16px;
}

.pricing-main-price {
  font-size: 40px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.1;
  margin-bottom: 18px;
}

.pricing-main-scene {
  padding: 12px 14px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 18px;
}

/* 右侧四条辅助幅 (#115 - #119, #123) */
.pricing-aux-stack {
  display: flex;
  flex-direction: column;
  border-left: 1px solid var(--border);
  background-color: var(--surface);
}

.pricing-aux-row {
  display: grid;
  grid-template-columns: 52px 1.1fr 0.9fr 0.9fr 1.6fr auto;
  align-items: center;
  gap: 14px;
  min-height: 108px;
  padding: 18px 28px;
  border-bottom: 1px solid var(--border);
}

.pricing-aux-row:last-child {
  border-bottom: none;
}

.aux-num {
  font-size: 22px;
  font-weight: 600;
  color: var(--muted);
}

.aux-name {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
}

.aux-vol {
  font-size: 16px;
  font-weight: 600;
  color: var(--blue-dark);
}

.aux-price {
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
}

.aux-desc {
  font-size: 14px;
  color: var(--body);
}

.pricing-disclaimer {
  margin-top: 14px;
  font-size: 13px;
  color: var(--muted);
}

/* ==========================================================================
   第八幅：山水云机场深度评测分幅 (65% / 35% #127 - #136)
   ========================================================================== */
.grid-review {
  display: grid;
  grid-template-columns: 65fr 35fr;
}

.review-conclusion-box {
  padding: 18px 20px;
  background-color: var(--tint-warm);
  border-left: 3px solid var(--stone);
  margin: 18px 0;
  color: var(--text);
  font-size: 16px;
}

.review-scope-tags {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin: 20px 0 24px;
}

.scope-tag-item {
  padding: 10px 12px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  font-size: 14px;
}

.scope-tag-item strong {
  display: block;
  color: var(--text);
}

.review-toc-list {
  display: flex;
  flex-direction: column;
}

.review-toc-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 11px 0;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
  color: var(--text);
}

.review-toc-item:hover {
  color: var(--accent);
  padding-left: 3px;
}

/* ==========================================================================
   第九幅：阅读分幅（连续4幅，拒绝九宫格 #137 - #146）
   ========================================================================== */
.reading-bands-stack {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.reading-band-1 {
  display: grid;
  grid-template-columns: 70fr 30fr;
}

.reading-band-2 {
  display: grid;
  grid-template-columns: 58fr 42fr;
}

.reading-band-3 {
  display: grid;
  grid-template-columns: 42fr 29fr 29fr;
}

.reading-band-4 {
  display: grid;
  grid-template-columns: 40fr 32fr 28fr;
}

.article-entry {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  height: 100%;
}

.article-meta-top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 10px;
}

.article-entry h3 {
  font-size: 20px;
  margin-bottom: 10px;
  line-height: 1.4;
}

.article-entry h3 a:hover {
  color: var(--blue);
}

.article-excerpt {
  font-size: 15px;
  color: var(--body);
  margin-bottom: 18px;
}

.article-meta-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--muted);
}

.category-nav-strip {
  margin-top: 20px;
  display: grid;
  grid-template-columns: 28fr 18fr 18fr 18fr 18fr;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.cat-strip-cell {
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 15px;
  font-weight: 600;
}

.cat-strip-cell + .cat-strip-cell {
  border-left: 1px solid var(--border);
}

/* ==========================================================================
   第十幅：网络排障分幅 (44% / 33% / 23% #154 - #169)
   ========================================================================== */
.grid-troubleshoot {
  display: grid;
  grid-template-columns: 44fr 33fr 23fr;
}

.ts-group-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.ts-item {
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

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

.ts-item h3 {
  font-size: 18px;
  margin-bottom: 6px;
}

.ts-item p {
  font-size: 14px;
}

/* ==========================================================================
   第十一幅：FAQ三大区域横幅 (36% / 34% / 30% #170 - #178)
   ========================================================================== */
.grid-faq {
  display: grid;
  grid-template-columns: 36fr 34fr 30fr;
}

.faq-list {
  display: flex;
  flex-direction: column;
}

.faq-item {
  border-bottom: 1px solid var(--border);
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-trigger {
  width: 100%;
  display: grid;
  grid-template-columns: 38px 1fr 20px;
  align-items: baseline;
  text-align: left;
  padding: 14px 0;
  gap: 6px;
  color: var(--text);
  font-weight: 600;
  font-size: 15px;
  line-height: 1.5;
}

.faq-trigger:hover {
  color: var(--blue);
}

.faq-qnum {
  font-size: 12px;
  font-weight: 700;
  color: var(--stone);
}

.faq-icon {
  font-size: 16px;
  color: var(--muted);
  text-align: right;
  transition: transform 0.18s ease;
}

.faq-trigger[aria-expanded="true"] .faq-icon {
  transform: rotate(45deg);
  color: var(--accent);
}

.faq-answer {
  padding: 0 0 16px 38px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--body);
}

/* 仅在JS启用且折叠时隐藏答案，保证JS关闭时全部可见 (#211, #291) */
html.js-enabled .faq-item:not(.is-open) .faq-answer {
  display: none;
}

.faq-bottom-cta {
  display: grid;
  grid-template-columns: 68fr 32fr;
  align-items: center;
  margin-top: 20px;
  background-color: var(--tint-green);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 32px;
  gap: 20px;
}

/* ==========================================================================
   Footer 最后一幅 (38% / 22% / 20% / 20% #218 - #229)
   ========================================================================== */
.site-footer {
  background-color: var(--surface-alt);
  color: var(--footer-text);
  border-top: 1px solid var(--border);
  padding: 36px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 38fr 22fr 20fr 20fr;
  border: 1px solid var(--border);
  background-color: var(--bg);
  border-radius: var(--radius);
}

.footer-col {
  padding: 26px 26px;
}

.footer-col + .footer-col {
  border-left: 1px solid var(--border);
}

.footer-col-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.footer-links a {
  font-size: 14px;
  color: var(--footer-text);
}

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

.footer-meta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
  font-size: 13px;
}

.footer-meta-links a {
  color: var(--footer-text);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-top: 20px;
  font-size: 13px;
  color: var(--footer-text);
}

.friend-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
}

.friend-links a {
  color: var(--footer-text);
  border-bottom: 1px solid var(--border);
}

.friend-links a:hover {
  color: var(--text);
  border-bottom-color: var(--text);
}

/* ==========================================================================
   分类页与文章页样式 (#147 - #153, #179 - #188)
   ========================================================================== */
.breadcrumb-bar {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  background-color: var(--bg);
  font-size: 13px;
  color: var(--muted);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb-list a {
  color: var(--body);
}

.breadcrumb-list a:hover {
  color: var(--text);
}

/* 分类/文章顶部68/32短横幅 (#150, #151, #181) */
.subpage-hero-frame {
  display: grid;
  grid-template-columns: 68fr 32fr;
  min-height: 230px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin: 28px 0;
}

.subpage-hero-main {
  padding: 36px 38px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.subpage-hero-main h1 {
  font-size: clamp(28px, 2.8vw, 40px);
  margin: 10px 0 14px;
}

.subpage-hero-side {
  padding: 32px 28px;
  background-color: var(--surface-alt);
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 10px;
  font-size: 14px;
}

.meta-kv {
  display: flex;
  justify-content: space-between;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.meta-kv:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

/* 文章主体与右侧轻量目录 (#179, #186) */
.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 800px) 230px;
  justify-content: space-between;
  gap: 40px;
  padding-bottom: 56px;
}

.article-main {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 44px 48px;
  max-width: 820px;
}

.quick-conclusion {
  padding: 22px 24px;
  background-color: var(--tint-green);
  border: 1px solid var(--border);
  border-left: 4px solid var(--green-dark);
  margin-bottom: 34px;
}

.quick-conclusion-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--green-dark);
  margin-bottom: 8px;
}

.article-content h2 {
  margin-top: 40px;
  margin-bottom: 16px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
  font-size: clamp(22px, 2.1vw, 28px);
}

.article-content h2 .h2-num {
  display: block;
  font-size: 12px;
  font-weight: 700;
  color: var(--stone);
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}

.article-content h3 {
  margin-top: 24px;
  margin-bottom: 10px;
  font-size: 19px;
}

.article-content p {
  margin-bottom: 16px;
  color: var(--body);
}

.article-content ul,
.article-content ol {
  margin: 14px 0 20px 20px;
}

.article-content ul li {
  list-style: disc;
  margin-bottom: 8px;
}

.article-content ol li {
  list-style: decimal;
  margin-bottom: 8px;
}

.article-callout {
  padding: 18px 20px;
  background-color: var(--bg);
  border: 1px solid var(--border);
  margin: 22px 0;
  font-size: 15px;
}

/* 右侧轻量目录 (#186) */
.article-sidebar {
  width: 230px;
}

.toc-box {
  position: sticky;
  top: 94px;
  padding: 20px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.toc-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.toc-nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
}

.toc-nav a {
  color: var(--body);
  line-height: 1.45;
}

.toc-nav a:hover {
  color: var(--blue);
}

.mobile-toc-details {
  display: none;
  margin-bottom: 24px;
  background-color: var(--bg);
  border: 1px solid var(--border);
  padding: 12px 16px;
}

.mobile-toc-details summary {
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
}

/* 文章底部内链与上一篇/下一篇 (#188, #204) */
.article-footer-nav {
  margin-top: 40px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.prev-next-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  border: 1px solid var(--border);
  margin-bottom: 28px;
}

.prev-next-cell {
  padding: 18px 20px;
}

.prev-next-cell + .prev-next-cell {
  border-left: 1px solid var(--border);
}

.prev-next-cell span {
  display: block;
  font-size: 12px;
  color: var(--muted);
  margin-bottom: 4px;
}

.prev-next-cell a {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

/* 分类页稳定纵向列表 (#153) */
.category-list-frame {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-top: 20px;
}

.category-list-row {
  display: grid;
  grid-template-columns: 68fr 32fr;
  padding: 26px 32px;
  border-bottom: 1px solid var(--border);
  gap: 24px;
  align-items: center;
}

.category-list-row:last-child {
  border-bottom: none;
}

/* ==========================================================================
   响应式适配：1024px / 768px / 430px / 390px / 375px (#242 - #253, #270)
   ========================================================================== */
@media (max-width: 1120px) {
  .main-nav {
    gap: 14px;
  }
  .nav-link {
    font-size: 13px;
  }
  .pricing-aux-row {
    grid-template-columns: 40px 1fr 0.9fr 0.9fr;
  }
  .pricing-aux-row .aux-desc {
    grid-column: 2 / -1;
  }
}

@media (max-width: 960px) {
  .main-nav {
    display: none;
  }
  .mobile-menu-btn {
    display: inline-flex;
  }
  .article-layout {
    grid-template-columns: 1fr;
  }
  .article-sidebar {
    display: none;
  }
  .mobile-toc-details {
    display: block;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }

  .brand-sub {
    display: none;
  }

  .header-actions .btn-primary {
    display: none;
  }

  .scroll-section {
    padding: 32px 0;
  }

  .section-head-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  /* 移动端所有横向分幅转换为纵向1fr (#44, #243, #274) */
  .hero-frame,
  .grid-plans,
  .grid-nodes,
  .grid-lines,
  .grid-ai-stream,
  .grid-clients,
  .pricing-frame,
  .grid-review,
  .reading-band-1,
  .reading-band-2,
  .reading-band-3,
  .reading-band-4,
  .category-nav-strip,
  .grid-troubleshoot,
  .grid-faq,
  .faq-bottom-cta,
  .footer-grid,
  .subpage-hero-frame,
  .category-list-row,
  .prev-next-grid,
  .os-dual-grid,
  .line-qa-grid {
    grid-template-columns: 1fr;
  }

  .hero-frame {
    min-height: auto;
  }

  .hero-pane-main,
  .hero-pane-mid,
  .hero-pane-right,
  .band-pane,
  .pricing-main-band,
  .subpage-hero-main,
  .subpage-hero-side,
  .article-main {
    padding: 24px 20px;
  }

  .band-pane + .band-pane,
  .hero-pane-mid,
  .hero-pane-right,
  .pricing-aux-stack,
  .footer-col + .footer-col,
  .subpage-hero-side,
  .cat-strip-cell + .cat-strip-cell,
  .prev-next-cell + .prev-next-cell {
    border-left: none;
    border-top: 1px solid var(--border);
  }

  .platform-factors,
  .review-scope-tags {
    grid-template-columns: 1fr;
  }

  .compact-platform-line {
    flex-direction: column;
    gap: 2px;
  }

  /* Mobile价格顺序：主力方案 ↓ 日常方案 ↓ 轻量方案 ↓ 高频方案 ↓ 长期方案 (#126, #251) */
  .pricing-aux-row {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    padding: 20px;
  }
  .pricing-aux-row.plan-row-02 {
    order: 1;
  }
  .pricing-aux-row.plan-row-01 {
    order: 2;
  }
  .pricing-aux-row.plan-row-04 {
    order: 3;
  }
  .pricing-aux-row.plan-row-05 {
    order: 4;
  }

  /* Mobile表格转换为块状阅读 (#85, #300.80) */
  .band-table-wrap {
    padding: 20px;
  }
  .editorial-table,
  .editorial-table thead,
  .editorial-table tbody,
  .editorial-table tr,
  .editorial-table td {
    display: block;
    width: 100%;
  }
  .editorial-table thead {
    display: none;
  }
  .editorial-table tr {
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
  }
  .editorial-table tr:last-child {
    border-bottom: none;
  }
  .editorial-table td {
    border-bottom: none;
    padding: 4px 0;
    white-space: normal;
  }
  .editorial-table td::before {
    content: attr(data-label) "：";
    font-weight: 600;
    color: var(--muted);
  }

  /* Mobile Footer顺序 (#253) */
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* 减弱动态效果支持 (#241, #292) */
@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;
  }
  .btn-primary:hover .arrow,
  .btn-secondary:hover .arrow,
  .link-arrow:hover .arrow,
  .review-toc-item:hover {
    transform: none !important;
    padding-left: 0 !important;
  }
}