/* 蛙爪云 - 抓点角标系统 全站样式表 */
:root {
  --bg: #F8F9F7;
  --surface: #FFFFFF;
  --surface-soft: #F0F2F0;
  --text: #1E2932;
  --muted: #5C6870;
  --subtle: #879198;
  --navy: #27475B;
  --navy-dark: #1E3747;
  --navy-mid: #416377;
  --moss: #657567;
  --moss-dark: #4F5F52;
  --moss-soft: #EDF1EC;
  --amber: #B38243;
  --amber-dark: #906730;
  --amber-soft: #F6EFE4;
  --border: #DCE2DF;
  --corner-line: #AAB8B2;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  --max-width: 1200px;
  --article-width: 780px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-family);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.8;
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

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

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

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

:focus-visible {
  outline: 2px solid var(--navy-mid);
  outline-offset: 3px;
}

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

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

.section:last-of-type {
  border-bottom: none;
}

/* 抓点角标核心样式 (L形短线，非封闭矩形) */
.corner-box {
  position: relative;
  background: var(--surface);
  padding: 24px 28px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.corner-box::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  width: 24px;
  height: 24px;
  border-top: 2px solid var(--corner-line);
  border-left: 2px solid var(--corner-line);
  transition: var(--transition);
  pointer-events: none;
}

.corner-box::after {
  content: '';
  position: absolute;
  bottom: -2px;
  right: -2px;
  width: 24px;
  height: 24px;
  border-bottom: 2px solid var(--corner-line);
  border-right: 2px solid var(--corner-line);
  transition: var(--transition);
  pointer-events: none;
}

/* 角标变体与特化 */
.corner-box.corner-moss::before,
.corner-box.corner-moss::after {
  border-color: var(--moss);
}

.corner-box.corner-amber::before,
.corner-box.corner-amber::after {
  border-color: var(--amber);
}

.corner-box.corner-navy::before,
.corner-box.corner-navy::after {
  border-color: var(--navy);
}

.corner-box:hover::before {
  width: 32px;
  height: 32px;
}

.corner-box:hover::after {
  width: 32px;
  height: 32px;
}

/* 独立L形标记 */
.corner-mark {
  display: inline-block;
  position: relative;
  padding: 2px 6px;
}

.corner-mark-tl {
  position: absolute;
  top: -4px;
  left: -4px;
  width: 12px;
  height: 12px;
  border-top: 2px solid var(--moss);
  border-left: 2px solid var(--moss);
}

.corner-mark-br {
  position: absolute;
  bottom: -4px;
  right: -4px;
  width: 12px;
  height: 12px;
  border-bottom: 2px solid var(--moss);
  border-right: 2px solid var(--moss);
}

/* Header */
.site-header {
  height: 72px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
}

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

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

.logo-symbol {
  width: 36px;
  height: 36px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 14px;
  letter-spacing: 1px;
  color: var(--navy);
  background: var(--surface);
  border-radius: var(--radius-sm);
}

.logo-symbol::before {
  content: '';
  position: absolute;
  top: -1px;
  left: -1px;
  width: 10px;
  height: 10px;
  border-top: 2px solid var(--moss);
  border-left: 2px solid var(--moss);
}

.logo-symbol::after {
  content: '';
  position: absolute;
  bottom: -1px;
  right: -1px;
  width: 10px;
  height: 10px;
  border-bottom: 2px solid var(--moss);
  border-right: 2px solid var(--moss);
}

.logo-tr-dot {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 4px;
  height: 4px;
  background-color: var(--amber);
  border-radius: 50%;
}

.brand-text-wrap {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy-dark);
  line-height: 1.2;
}

.brand-sub {
  font-size: 11px;
  color: var(--subtle);
  letter-spacing: 0.5px;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 20px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  position: relative;
  padding: 6px 4px;
}

.nav-link:hover, .nav-link.active {
  color: var(--navy-dark);
}

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

.nav-link.active .active-corner {
  position: absolute;
  top: -2px;
  right: -4px;
  width: 6px;
  height: 6px;
  border-top: 2px solid var(--moss);
  border-right: 2px solid var(--moss);
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--navy);
  color: var(--surface);
  padding: 9px 18px;
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.header-cta:hover {
  background: var(--navy-dark);
  color: var(--surface);
  transform: translateY(-1px);
}

.header-cta .arrow {
  transition: transform 0.2s ease;
}

.header-cta:hover .arrow {
  transform: translateX(3px);
}

.mobile-menu-btn {
  display: none;
  padding: 8px;
  color: var(--navy);
}

/* Hero Section */
.hero-section {
  padding: 64px 0 80px 0;
  background: var(--bg);
  position: relative;
  min-height: 640px;
  max-height: 760px;
  display: flex;
  align-items: center;
  border-bottom: 1px solid var(--border);
}

.hero-layout {
  position: relative;
  width: 100%;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 40px;
  align-items: center;
}

.hero-center-content {
  z-index: 2;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--moss-dark);
  background: var(--moss-soft);
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  font-weight: 600;
}

.hero-title {
  font-size: 44px;
  line-height: 1.2;
  color: var(--navy-dark);
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.hero-lead-text {
  font-size: 20px;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 16px;
}

.hero-desc {
  font-size: 16px;
  color: var(--muted);
  line-height: 1.8;
  margin-bottom: 32px;
  max-width: 580px;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--navy);
  color: var(--surface);
  padding: 12px 28px;
  font-size: 16px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.btn-primary:hover {
  background: var(--navy-dark);
  color: var(--surface);
  transform: translateY(-2px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--surface);
  color: var(--navy-dark);
  border: 1px solid var(--border);
  padding: 12px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.btn-secondary:hover {
  border-color: var(--navy);
  color: var(--navy);
}

.hero-keypoints-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  position: relative;
}

.hero-kp-card {
  background: var(--surface);
  padding: 20px 22px;
  position: relative;
}

.hero-kp-card:nth-child(5) {
  grid-column: span 2;
}

.kp-num {
  font-size: 12px;
  font-weight: 700;
  color: var(--moss);
  letter-spacing: 1px;
  margin-bottom: 4px;
  display: block;
}

.kp-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 6px;
}

.kp-items {
  font-size: 13px;
  font-weight: 600;
  color: var(--navy-mid);
  margin-bottom: 6px;
}

.kp-sub {
  font-size: 12px;
  color: var(--subtle);
  line-height: 1.5;
}

/* Section Header Structure */
.section-header {
  margin-bottom: 40px;
}

.section-tag {
  font-size: 13px;
  font-weight: 700;
  color: var(--moss);
  letter-spacing: 1px;
  margin-bottom: 8px;
  display: inline-block;
}

.section-h2 {
  font-size: 32px;
  color: var(--navy-dark);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 12px;
}

.section-intro {
  font-size: 17px;
  color: var(--muted);
  max-width: 800px;
  line-height: 1.8;
}

/* 01. 需求抓点区 */
.needs-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.need-item {
  background: var(--surface);
  padding: 28px 32px;
}

.need-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--surface-soft);
  padding-bottom: 12px;
}

.need-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy-dark);
}

.need-tags {
  font-size: 13px;
  color: var(--amber-dark);
  background: var(--amber-soft);
  padding: 2px 10px;
  border-radius: 2px;
  font-weight: 600;
}

.need-desc {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 16px;
  line-height: 1.7;
}

.need-focus {
  font-size: 14px;
  color: var(--navy);
  background: var(--bg);
  padding: 10px 14px;
  border-left: 3px solid var(--moss);
}

/* 02. 流量抓点行 */
.data-rows {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.data-row-item {
  display: grid;
  grid-template-columns: 120px 160px 1fr 1fr;
  align-items: center;
  gap: 20px;
  background: var(--surface);
  padding: 22px 28px;
}

.data-amount {
  font-size: 28px;
  font-weight: 800;
  color: var(--navy-dark);
  line-height: 1;
}

.data-target {
  font-size: 16px;
  font-weight: 700;
  color: var(--moss-dark);
}

.data-fit {
  font-size: 14px;
  color: var(--muted);
}

.data-factors {
  font-size: 13px;
  color: var(--subtle);
  border-left: 1px solid var(--border);
  padding-left: 16px;
}

/* 03. 地区重点标记 */
.region-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.region-item {
  background: var(--surface);
  padding: 28px 32px;
}

.region-title-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.region-name {
  font-size: 22px;
  font-weight: 800;
  color: var(--navy-dark);
}

.region-badge {
  font-size: 12px;
  padding: 2px 8px;
  background: var(--moss-soft);
  color: var(--moss-dark);
  font-weight: 600;
}

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

.region-note {
  font-size: 13px;
  color: var(--amber-dark);
  background: var(--amber-soft);
  padding: 10px 14px;
  border-radius: var(--radius-sm);
}

/* 04. 线路知识与HTML表格 */
.line-summary-text {
  font-size: 16px;
  color: var(--muted);
  margin-bottom: 24px;
  line-height: 1.8;
}

.line-table-wrapper {
  overflow-x: auto;
  margin-bottom: 24px;
}

.line-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  text-align: left;
}

.line-table th {
  background: var(--surface-soft);
  color: var(--navy-dark);
  font-weight: 700;
  font-size: 15px;
  padding: 16px 20px;
  border-bottom: 2px solid var(--border);
}

.line-table td {
  padding: 18px 20px;
  font-size: 14px;
  color: var(--text);
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

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

.line-type-name {
  font-weight: 700;
  color: var(--navy-dark);
  font-size: 16px;
}

.qa-box {
  background: var(--surface);
  padding: 24px 28px;
  margin-top: 24px;
}

.qa-q {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 8px;
}

.qa-a {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.7;
}

/* 05. AI与流媒体重点对照 */
.compare-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.compare-column {
  background: var(--surface);
  padding: 32px;
}

.compare-h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.compare-cover {
  font-size: 13px;
  color: var(--moss);
  font-weight: 600;
  margin-bottom: 16px;
}

.compare-list {
  list-style: none;
  margin-bottom: 20px;
}

.compare-list li {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 10px;
  padding-left: 20px;
  position: relative;
}

.compare-list li::before {
  content: '■';
  position: absolute;
  left: 0;
  color: var(--moss);
  font-size: 10px;
  top: 4px;
}

.shared-factors-bar {
  grid-column: span 2;
  background: var(--moss-soft);
  padding: 20px 24px;
  border-left: 4px solid var(--moss);
  font-size: 14px;
  color: var(--navy-dark);
  line-height: 1.7;
}

/* 06. 设备重点目录 */
.device-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.device-item {
  background: var(--surface);
  padding: 28px 32px;
}

.device-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 12px;
}

.device-sec-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--subtle);
  margin-top: 12px;
  margin-bottom: 4px;
  text-transform: uppercase;
}

.device-p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
}

/* 07. 完整套餐价格 (角标价目) */
.pricing-section-wrap {
  background: var(--surface-soft);
  padding: 48px 36px;
  position: relative;
}

.pricing-notice-banner {
  font-size: 13px;
  color: var(--subtle);
  background: var(--surface);
  padding: 10px 16px;
  border-left: 3px solid var(--amber);
  margin-bottom: 32px;
}

.pricing-stagger-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: stretch;
}

.pricing-card {
  background: var(--surface);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
}

.pricing-card.featured {
  background: var(--moss-soft);
  transform: translateY(-8px);
}

.pricing-card.featured::before,
.pricing-card.featured::after {
  border-color: var(--moss-dark);
}

.plan-badge-amber {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--amber);
  color: var(--surface);
  font-size: 12px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 2px;
}

.plan-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 8px;
}

.plan-data {
  font-size: 15px;
  font-weight: 700;
  color: var(--moss-dark);
  margin-bottom: 16px;
}

.plan-price-wrap {
  margin-bottom: 24px;
}

.plan-price {
  font-size: 38px;
  font-weight: 800;
  color: var(--navy-dark);
  line-height: 1;
}

.plan-period {
  font-size: 14px;
  color: var(--subtle);
}

.plan-features {
  list-style: none;
  margin-bottom: 28px;
  flex: 1;
}

.plan-features li {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 8px;
  padding-left: 16px;
  position: relative;
}

.plan-features li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--navy);
  font-weight: 700;
}

.plan-btn {
  display: block;
  text-align: center;
  padding: 12px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  background: var(--navy);
  color: var(--surface);
  transition: var(--transition);
}

.plan-btn:hover {
  background: var(--navy-dark);
  color: var(--surface);
}

.pricing-card.featured .plan-btn {
  background: var(--amber-dark);
}

.pricing-card.featured .plan-btn:hover {
  background: var(--amber);
}

/* 08. 蛙爪云深度评测 */
.review-teaser-box {
  background: var(--surface);
  padding: 40px;
  position: relative;
}

.review-teaser-header {
  margin-bottom: 24px;
}

.review-teaser-title {
  font-size: 26px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 12px;
}

.review-teaser-lead {
  font-size: 16px;
  color: var(--muted);
  line-height: 1.8;
  margin-bottom: 24px;
}

.review-key-tags {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.rt-tag {
  font-size: 13px;
  font-weight: 600;
  color: var(--navy);
  background: var(--surface-soft);
  padding: 6px 14px;
  border-left: 2px solid var(--moss);
}

/* 09. 网络问题快速判断 */
.trouble-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}

.trouble-item {
  background: var(--surface);
  padding: 20px 18px;
}

.trouble-step {
  font-size: 12px;
  font-weight: 700;
  color: var(--amber-dark);
  margin-bottom: 6px;
}

.trouble-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 8px;
}

.trouble-desc {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

.trouble-dns-note {
  margin-top: 24px;
  background: var(--amber-soft);
  padding: 16px 20px;
  font-size: 14px;
  color: var(--amber-dark);
  border-left: 3px solid var(--amber);
}

/* 10. 快速判断文章中心 */
.articles-index-layout {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.featured-article-card {
  background: var(--surface);
  padding: 36px;
  border-left: 4px solid var(--navy);
}

.featured-art-title {
  font-size: 24px;
  font-weight: 800;
  color: var(--navy-dark);
  margin-bottom: 12px;
}

.featured-art-desc {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 20px;
  line-height: 1.8;
}

.articles-list-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.art-item-card {
  background: var(--surface);
  padding: 24px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.art-item-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--subtle);
  margin-bottom: 10px;
}

.art-item-cat {
  color: var(--moss-dark);
  font-weight: 700;
}

.art-item-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 8px;
  line-height: 1.4;
}

.art-item-answer {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 16px;
  line-height: 1.6;
}

.art-read-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--navy);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.art-read-link:hover {
  color: var(--moss);
}

/* 11. FAQ (问题重点索引) */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

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

.faq-toggle-btn {
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 17px;
  font-weight: 700;
  color: var(--navy-dark);
  gap: 16px;
}

.faq-toggle-btn:hover {
  color: var(--moss);
}

.faq-icon {
  font-size: 20px;
  color: var(--subtle);
  font-weight: 400;
  transition: transform 0.25s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  color: var(--navy);
}

.faq-answer {
  display: none;
  padding: 0 24px 20px 24px;
  font-size: 15px;
  color: var(--muted);
  line-height: 1.8;
}

.faq-item.active .faq-answer {
  display: block;
}

/* Footer (浅苔灰重点目录型) */
.site-footer {
  background: var(--moss-soft);
  border-top: 1px solid var(--border);
  padding: 56px 0 32px 0;
  color: var(--navy-dark);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(4, 1fr);
  gap: 32px;
  margin-bottom: 48px;
}

.footer-brand-info {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-logo-title {
  font-size: 20px;
  font-weight: 800;
  color: var(--navy-dark);
}

.footer-tagline {
  font-size: 13px;
  color: var(--moss-dark);
  font-weight: 600;
}

.footer-desc {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.7;
}

.footer-col-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.footer-col-title .mini-corner {
  width: 6px;
  height: 6px;
  border-top: 2px solid var(--moss);
  border-left: 2px solid var(--moss);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

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

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

.footer-bottom-bar {
  border-top: 1px solid var(--border);
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: var(--subtle);
}

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

.friend-links span {
  font-weight: 600;
  color: var(--navy-mid);
}

.friend-links a {
  color: var(--muted);
}

.friend-links a:hover {
  color: var(--navy);
}

/* 分类页与文章页结构通用 */
.page-header {
  padding: 48px 0 32px 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--subtle);
  margin-bottom: 16px;
}

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

.page-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--navy-dark);
  line-height: 1.3;
  margin-bottom: 12px;
}

.page-intro {
  font-size: 16px;
  color: var(--muted);
  max-width: 800px;
  line-height: 1.8;
}

.article-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 48px 24px;
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 48px;
}

.article-body-wrap {
  max-width: var(--article-width);
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 13px;
  color: var(--subtle);
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.article-quick-summary {
  background: var(--surface);
  padding: 24px 28px;
  margin-bottom: 36px;
  position: relative;
}

.quick-summary-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.quick-summary-text {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.8;
}

/* GEO文章内容样式 */
.article-content h2 {
  font-size: 24px;
  font-weight: 800;
  color: var(--navy-dark);
  margin: 40px 0 16px 0;
  line-height: 1.4;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--surface-soft);
}

.article-content h3 {
  font-size: 19px;
  font-weight: 700;
  color: var(--navy);
  margin: 28px 0 12px 0;
}

.article-content p {
  font-size: 16.5px;
  color: var(--text);
  line-height: 1.85;
  margin-bottom: 20px;
}

.article-content ul, .article-content ol {
  margin: 0 0 24px 24px;
  color: var(--text);
  line-height: 1.8;
}

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

.article-content blockquote {
  background: var(--moss-soft);
  border-left: 4px solid var(--moss);
  padding: 16px 20px;
  font-style: normal;
  font-size: 15px;
  color: var(--navy-dark);
  margin: 24px 0;
}

.related-articles-box {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 2px solid var(--border);
}

.related-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 16px;
}

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

.related-links-list a {
  font-size: 15px;
  font-weight: 600;
  color: var(--navy);
  display: flex;
  align-items: center;
  gap: 8px;
}

.related-links-list a:hover {
  color: var(--moss);
}

/* 文章目录 Sidebar */
.toc-sidebar {
  position: sticky;
  top: 96px;
  align-self: start;
}

.toc-card {
  background: var(--surface);
  padding: 20px 24px;
  border-radius: var(--radius-sm);
}

.toc-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 12px;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toc-list a {
  font-size: 13.5px;
  color: var(--muted);
  line-height: 1.4;
  display: block;
}

.toc-list a:hover {
  color: var(--navy);
}

/* Sitemap Page & Misc Pages */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 32px;
}

.sitemap-group {
  background: var(--surface);
  padding: 24px;
}

.sitemap-group-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy-dark);
  margin-bottom: 16px;
  border-bottom: 1px solid var(--surface-soft);
  padding-bottom: 8px;
}

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

.sitemap-links a {
  font-size: 14.5px;
  color: var(--navy);
}

/* 404 Page */
.error-404-wrap {
  text-align: center;
  padding: 96px 24px;
}

.error-code {
  font-size: 72px;
  font-weight: 900;
  color: var(--navy-dark);
  line-height: 1;
  margin-bottom: 16px;
}

.error-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 24px;
}

.error-links {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* prefers-reduced-motion */
@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;
  }
}

/* Responsive Rules (375px, 390px, 430px, 768px, 1024px, 1440px) */
@media (max-width: 1024px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .hero-section {
    max-height: none;
    min-height: auto;
    padding: 48px 0;
  }
  .article-container {
    grid-template-columns: 1fr;
  }
  .toc-sidebar {
    display: none;
  }
  .pricing-stagger-grid {
    grid-template-columns: 1fr 1fr;
  }
  .trouble-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-desktop {
    display: none;
  }
  .mobile-menu-btn {
    display: block;
  }
  .mobile-nav-drawer {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 20px 24px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.05);
    z-index: 999;
  }
  .mobile-nav-drawer.active {
    display: flex;
    flex-direction: column;
    gap: 14px;
  }
  .mobile-nav-link {
    font-size: 16px;
    font-weight: 600;
    color: var(--navy-dark);
    padding: 8px 0;
    border-bottom: 1px solid var(--surface-soft);
  }
  .hero-title {
    font-size: 32px;
  }
  .hero-keypoints-grid {
    grid-template-columns: 1fr;
  }
  .hero-kp-card:nth-child(5) {
    grid-column: auto;
  }
  .needs-grid, .region-grid, .compare-layout, .device-grid, .articles-list-grid, .sitemap-grid {
    grid-template-columns: 1fr;
  }
  .shared-factors-bar {
    grid-column: auto;
  }
  .data-row-item {
    grid-template-columns: 1fr;
    gap: 8px;
    align-items: start;
  }
  .data-factors {
    border-left: none;
    padding-left: 0;
  }
  .pricing-stagger-grid {
    grid-template-columns: 1fr;
  }
  .pricing-card.featured {
    transform: none;
  }
  .trouble-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}