/* ==========================================================================
   八戒云 - “八向云路矩阵” Design System
   Color Palette:
   - Main Background: #F5F8FA
   - Pure White: #FFFFFF
   - Light Background: #EEF3F5
   - Main Text: #17242D
   - Body Text: #52606A
   - Secondary Text: #829099
   - Main Teal (主青): #287C82
   - Main Blue (主蓝): #386FD1
   - Light Teal (浅青): #5AA89F
   - Accent Orange (强调橙): #D58A4B
   - Border: #D9E3E6
   - Light Blue Bg: #EEF4FB
   - Light Teal Bg: #EDF7F5
   - Footer Bg: #EDF3F4
   ========================================================================== */

:root {
  --bg-main: #F5F8FA;
  --bg-white: #FFFFFF;
  --bg-light: #EEF3F5;
  --bg-light-blue: #EEF4FB;
  --bg-light-teal: #EDF7F5;
  --bg-footer: #EDF3F4;
  
  --text-primary: #17242D;
  --text-body: #52606A;
  --text-muted: #829099;
  
  --primary-teal: #287C82;
  --primary-blue: #386FD1;
  --teal-light: #5AA89F;
  --accent-orange: #D58A4B;
  --border-color: #D9E3E6;
  --border-dark: #B9C8CD;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  
  --shadow-sm: 0 1px 3px rgba(23, 36, 45, 0.04);
  --shadow-md: 0 4px 12px rgba(23, 36, 45, 0.06);
  --shadow-lg: 0 8px 24px rgba(23, 36, 45, 0.08);

  --transition-fast: 0.18s ease;
  --transition-normal: 0.25s ease;
}

*, *::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-main);
  color: var(--text-body);
  line-height: 1.68;
  font-weight: 400;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

img, svg {
  vertical-align: middle;
}

a {
  color: var(--primary-teal);
  text-decoration: none;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

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

ul, ol {
  list-style: none;
}

/* ==========================================================================
   Typography & Utilities
   ========================================================================== */

h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 600;
  line-height: 1.35;
}

.container {
  width: 100%;
  max-width: 1180px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

.section-spacer {
  padding-top: 72px;
  padding-bottom: 72px;
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  margin-bottom: 32px;
}

.section-index {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--primary-teal);
  letter-spacing: 1px;
  margin-bottom: 6px;
  padding: 2px 8px;
  background-color: var(--bg-light-teal);
  border: 1px solid rgba(40, 124, 130, 0.2);
  border-radius: var(--radius-sm);
}

.section-title {
  font-size: 26px;
  letter-spacing: -0.3px;
  color: var(--text-primary);
  margin-top: 4px;
}

.section-intro {
  margin-top: 10px;
  font-size: 15px;
  color: var(--text-body);
  max-width: 860px;
  line-height: 1.7;
}

/* ==========================================================================
   Buttons & CTA
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 600;
  padding: 9px 20px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
  gap: 6px;
}

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

.btn-primary:hover {
  background-color: #20676C;
  color: #FFFFFF;
  border-color: #20676C;
}

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

.btn-secondary:hover {
  background-color: var(--bg-light);
  border-color: var(--primary-teal);
  color: var(--primary-teal);
}

.btn-outline {
  background-color: transparent;
  color: var(--primary-teal);
  border-color: var(--primary-teal);
}

.btn-outline:hover {
  background-color: var(--bg-light-teal);
  color: var(--primary-teal);
}

.btn-arrow {
  display: inline-block;
  transition: transform var(--transition-fast);
}

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

/* ==========================================================================
   Header Navigation
   ========================================================================== */

.site-header {
  height: 70px;
  background-color: var(--bg-white);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
}

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

.header-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.brand-logo-svg {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

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

.brand-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.1;
  letter-spacing: -0.2px;
}

.brand-sub {
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.5px;
  margin-top: 2px;
}

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

.nav-link {
  font-size: 14px;
  color: var(--text-body);
  position: relative;
  padding: 6px 0;
  transition: color var(--transition-fast);
}

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

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

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--primary-teal);
  border-radius: 1px;
}

.header-cta {
  flex-shrink: 0;
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  padding: 7px 10px;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  cursor: pointer;
}

.mobile-nav-panel {
  display: none;
  position: absolute;
  top: 70px;
  left: 0;
  right: 0;
  background-color: var(--bg-white);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow-md);
  padding: 16px 20px 24px;
  flex-direction: column;
  gap: 12px;
}

.mobile-nav-panel.open {
  display: flex;
}

.mobile-nav-link {
  font-size: 15px;
  padding: 8px 0;
  border-bottom: 1px solid var(--bg-light);
  color: var(--text-primary);
}

/* ==========================================================================
   Hero: “八向云路矩阵”
   ========================================================================== */

.hero-section {
  background: linear-gradient(180deg, #FFFFFF 0%, #F5F8FA 100%);
  border-bottom: 1px solid var(--border-color);
  padding-top: 48px;
  padding-bottom: 48px;
  position: relative;
  overflow: hidden;
}

.hero-meta-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--primary-teal);
  background-color: var(--bg-light-teal);
  border: 1px solid rgba(40, 124, 130, 0.2);
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 16px;
  font-weight: 500;
}

.hero-meta-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--primary-teal);
}

.hero-h1 {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary-blue);
  letter-spacing: 0.5px;
  margin-bottom: 10px;
  text-transform: uppercase;
}

.hero-visual-title {
  font-size: 38px;
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  margin-bottom: 12px;
  letter-spacing: -0.5px;
}

.hero-subtitle {
  font-size: 16px;
  color: var(--text-muted);
  font-weight: 500;
  margin-bottom: 14px;
}

.hero-body-text {
  font-size: 15px;
  color: var(--text-body);
  max-width: 820px;
  margin-bottom: 24px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-bottom: 44px;
}

/* 8-Direction Cloud Route Matrix */
.matrix-container {
  position: relative;
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  box-shadow: var(--shadow-sm);
}

.matrix-header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 14px;
  margin-bottom: 28px;
}

.matrix-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.matrix-status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--primary-teal);
}

.matrix-legend {
  font-size: 12px;
  color: var(--text-muted);
}

/* Desktop Matrix Wheel & Spokes */
.matrix-canvas-wrap {
  position: relative;
  width: 100%;
  height: 380px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.matrix-center-node {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 140px;
  height: 140px;
  background: #FFFFFF;
  border: 2px solid var(--primary-teal);
  border-radius: 50%;
  box-shadow: 0 0 0 6px var(--bg-light-teal), var(--shadow-md);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 10;
  text-align: center;
  padding: 12px;
}

.center-node-logo {
  width: 38px;
  height: 38px;
  margin-bottom: 4px;
}

.center-node-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
}

.center-node-subtitle {
  font-size: 10px;
  color: var(--primary-teal);
  letter-spacing: 0.5px;
}

.matrix-spokes-svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 2;
}

.spoke-line {
  stroke: var(--border-color);
  stroke-width: 1.5;
  stroke-dasharray: 4, 3;
  transition: stroke var(--transition-fast), stroke-width var(--transition-fast);
}

.spoke-line.active,
.matrix-container:has(.matrix-item:hover) .spoke-line.active {
  stroke: var(--primary-teal);
  stroke-width: 2;
  stroke-dasharray: none;
}

/* 8 Direction Matrix Items in Desktop layout */
.matrix-spoke-grid {
  position: relative;
  width: 100%;
  height: 100%;
}

.matrix-item {
  position: absolute;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 8px 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  z-index: 5;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
  max-width: 165px;
}

.matrix-item:hover {
  border-color: var(--primary-teal);
  background-color: var(--bg-light-teal);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.item-index {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--text-muted);
  background-color: var(--bg-light);
  padding: 2px 5px;
  border-radius: 3px;
  transition: color var(--transition-fast), background var(--transition-fast);
}

.matrix-item:hover .item-index {
  color: #FFFFFF;
  background-color: var(--primary-teal);
}

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

.item-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

.matrix-item:hover .item-title {
  color: var(--primary-teal);
}

.item-sub {
  font-size: 10px;
  color: var(--text-muted);
}

/* Positions for 8 directions on 900x380 viewport */
.pos-01 { top: 12px; left: 50%; transform: translateX(-50%); } /* Hong Kong (North) */
.pos-02 { top: 38px; right: 8%; } /* Japan (North-East) */
.pos-03 { top: 50%; right: 2%; transform: translateY(-50%); } /* Singapore (East) */
.pos-04 { bottom: 38px; right: 8%; } /* US (South-East) */
.pos-05 { bottom: 12px; left: 50%; transform: translateX(-50%); } /* AI Tools (South) */
.pos-06 { bottom: 38px; left: 8%; } /* Streaming (South-West) */
.pos-07 { top: 50%; left: 2%; transform: translateY(-50%); } /* Clients (West) */
.pos-08 { top: 38px; left: 8%; } /* Troubleshooting (North-West) */

/* Mobile Matrix (2 cols x 4 rows) */
.matrix-mobile-grid {
  display: none;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-top: 16px;
}

.matrix-mobile-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
}

.matrix-mobile-card:hover {
  border-color: var(--primary-teal);
  background-color: var(--bg-light-teal);
}

/* ==========================================================================
   Matrix & Comparison Tables
   ========================================================================== */

.table-responsive {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-white);
  box-shadow: var(--shadow-sm);
}

.matrix-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 14px;
}

.matrix-table th {
  background-color: var(--bg-light);
  color: var(--text-primary);
  font-weight: 600;
  padding: 12px 18px;
  border-bottom: 1px solid var(--border-color);
  white-space: nowrap;
}

.matrix-table td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-body);
}

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

.matrix-table tbody tr:hover {
  background-color: var(--bg-light-teal);
}

.table-badge {
  display: inline-block;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 600;
}

.badge-teal {
  background-color: var(--bg-light-teal);
  color: var(--primary-teal);
  border: 1px solid rgba(40, 124, 130, 0.25);
}

.badge-blue {
  background-color: var(--bg-light-blue);
  color: var(--primary-blue);
  border: 1px solid rgba(56, 111, 209, 0.25);
}

.badge-orange {
  background-color: #FDF4EC;
  color: var(--accent-orange);
  border: 1px solid rgba(213, 138, 75, 0.25);
}

/* ==========================================================================
   Section 03: 亚洲节点 (3 行方向索引)
   ========================================================================== */

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

.direction-index-row {
  display: grid;
  grid-template-columns: 140px 180px 1fr 1fr;
  align-items: center;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  gap: 16px;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.direction-index-row:hover {
  border-color: var(--primary-teal);
  box-shadow: var(--shadow-sm);
}

.dir-meta {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--primary-teal);
}

.dir-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.dir-scene, .dir-focus {
  font-size: 14px;
  color: var(--text-body);
}

.dir-label {
  display: block;
  font-size: 11px;
  color: var(--text-muted);
  margin-bottom: 2px;
}

/* ==========================================================================
   Section 04: 美国节点 (独立重点条目)
   ========================================================================== */

.us-node-strip {
  display: grid;
  grid-template-columns: 200px 1.5fr 1fr;
  gap: 24px;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary-blue);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  align-items: center;
  box-shadow: var(--shadow-sm);
}

.us-left {
  display: flex;
  flex-direction: column;
}

.us-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
}

.us-tag {
  font-size: 12px;
  color: var(--primary-blue);
  margin-top: 4px;
}

.us-middle {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.us-service-chip {
  background-color: var(--bg-light-blue);
  border: 1px solid rgba(56, 111, 209, 0.2);
  color: var(--primary-blue);
  padding: 5px 12px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
}

.us-right {
  font-size: 13px;
  color: var(--text-body);
  border-left: 1px dashed var(--border-color);
  padding-left: 20px;
}

/* ==========================================================================
   Section 07: 客户端设备矩阵
   ========================================================================== */

.device-matrix-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.device-matrix-row {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 12px;
  transition: all var(--transition-fast);
}

.device-matrix-row:hover {
  border-color: var(--primary-teal);
  box-shadow: var(--shadow-sm);
}

.device-meta-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.device-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
}

.device-scope {
  font-size: 13px;
  color: var(--text-muted);
}

.device-link {
  font-size: 13px;
  font-weight: 600;
  color: var(--primary-teal);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* ==========================================================================
   Section 08: 资源等级套餐矩阵 (Pricing)
   ========================================================================== */

.pricing-resource-matrix {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.level-axis-layout {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 24px;
}

/* Left Level Axis */
.level-axis-rail {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  padding: 24px 0;
}

.level-axis-rail::before {
  content: "";
  position: absolute;
  top: 40px;
  bottom: 40px;
  left: 50%;
  width: 2px;
  background-color: var(--border-color);
  transform: translateX(-50%);
  z-index: 1;
}

.axis-node {
  position: relative;
  z-index: 2;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: var(--bg-white);
  border: 2px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--text-muted);
}

.axis-node.active-highlight {
  border-color: var(--primary-teal);
  background-color: var(--primary-teal);
  color: #FFFFFF;
  box-shadow: 0 0 0 4px var(--bg-light-teal);
}

/* Right Level Plans */
.level-plan-rows {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.plan-row-item {
  display: grid;
  grid-template-columns: 120px 150px 140px 1fr 140px;
  align-items: center;
  padding: 18px 24px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-white);
  gap: 16px;
  transition: all var(--transition-fast);
}

.plan-row-item:hover {
  border-color: var(--border-dark);
}

/* L3 Main Highlight */
.plan-row-item.plan-highlight {
  background-color: var(--bg-light-teal);
  border: 1px solid var(--primary-teal);
  border-left: 5px solid var(--primary-teal);
  box-shadow: var(--shadow-sm);
}

.plan-level-tag {
  display: flex;
  flex-direction: column;
}

.plan-code {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 800;
  color: var(--text-primary);
}

.plan-code.highlight-code {
  color: var(--primary-teal);
}

.plan-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.plan-badge-rec {
  display: inline-block;
  background-color: var(--primary-teal);
  color: #FFFFFF;
  font-size: 11px;
  font-weight: 600;
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  margin-top: 3px;
  width: fit-content;
}

.plan-traffic {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.plan-price-block {
  display: flex;
  align-items: baseline;
  gap: 3px;
}

.price-currency {
  font-size: 14px;
  color: var(--text-primary);
  font-weight: 600;
}

.price-amount {
  font-size: 22px;
  font-weight: 800;
  color: var(--text-primary);
}

.price-cycle {
  font-size: 12px;
  color: var(--text-muted);
}

.plan-fit {
  font-size: 13px;
  color: var(--text-body);
}

.plan-action {
  text-align: right;
}

/* Standalone Annual Plan */
.annual-plan-strip {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 20px 32px;
  display: grid;
  grid-template-columns: 140px 140px 140px 1fr 140px;
  align-items: center;
  gap: 16px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.annual-badge {
  background-color: #FDF4EC;
  color: var(--accent-orange);
  border: 1px solid rgba(213, 138, 75, 0.25);
  font-size: 12px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  width: fit-content;
}

/* Quick Pick Reference */
.quick-pick-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  background-color: var(--bg-light);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 14px 20px;
  align-items: center;
  font-size: 13px;
  color: var(--text-body);
}

.quick-pick-title {
  font-weight: 600;
  color: var(--text-primary);
  margin-right: 8px;
}

.quick-pick-item {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
}

.quick-pick-arrow {
  color: var(--primary-teal);
  font-weight: 700;
}

/* ==========================================================================
   Section 09: 深度评测区域
   ========================================================================== */

.review-highlight-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 32px;
  align-items: center;
}

.review-main-text h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

.review-main-text p {
  font-size: 15px;
  margin-bottom: 16px;
  line-height: 1.7;
}

.review-features-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  background-color: var(--bg-light);
  border: 1px solid var(--border-color);
  padding: 20px;
  border-radius: var(--radius-md);
}

.review-feature-point {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-body);
}

.feature-tick {
  color: var(--primary-teal);
  font-weight: 700;
}

/* ==========================================================================
   Section 10: 使用教程 (知识索引矩阵)
   ========================================================================== */

.knowledge-index-matrix {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.knowledge-matrix-header {
  display: grid;
  grid-template-columns: 140px 1fr 140px;
  background-color: var(--bg-light);
  padding: 12px 24px;
  border-bottom: 1px solid var(--border-color);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
}

.knowledge-matrix-row {
  display: grid;
  grid-template-columns: 140px 1fr 140px;
  padding: 16px 24px;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  transition: background-color var(--transition-fast);
  gap: 16px;
}

.knowledge-matrix-row:last-child {
  border-bottom: none;
}

.knowledge-matrix-row:hover {
  background-color: var(--bg-light-teal);
}

.km-category {
  font-size: 13px;
  font-weight: 500;
  color: var(--primary-teal);
}

.km-title-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.km-title-link:hover {
  color: var(--primary-teal);
}

.km-action {
  font-size: 13px;
  color: var(--text-muted);
  text-align: right;
  white-space: nowrap;
}

/* ==========================================================================
   Section 11: 网络排障 (Flow steps)
   ========================================================================== */

.troubleshoot-flow {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 10px;
  margin-bottom: 24px;
}

.ts-step-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px 12px;
  text-align: center;
  position: relative;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.ts-step-num {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--primary-teal);
  background-color: var(--bg-light-teal);
  padding: 2px 6px;
  border-radius: 3px;
  margin-bottom: 6px;
}

.ts-step-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.ts-step-detail {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 4px;
}

.troubleshoot-alert {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary-teal);
  padding: 16px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--text-body);
}

/* ==========================================================================
   Section 12: 常见问题 (节点问答索引)
   ========================================================================== */

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

.faq-item {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-fast);
}

.faq-item.active {
  border-color: var(--primary-teal);
}

.faq-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 22px;
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  gap: 16px;
}

.faq-title-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
}

.faq-index {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--primary-teal);
  background-color: var(--bg-light-teal);
  padding: 2px 7px;
  border-radius: 3px;
}

.faq-question {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
}

.faq-icon {
  font-size: 18px;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
}

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

.faq-content {
  display: none;
  padding: 0 22px 18px 52px;
  font-size: 14px;
  color: var(--text-body);
  line-height: 1.7;
  border-top: 1px dashed var(--border-color);
  margin-top: 4px;
  padding-top: 14px;
}

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

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  background-color: var(--bg-footer);
  border-top: 1px solid var(--border-color);
  padding-top: 40px;
  padding-bottom: 24px;
  margin-top: auto;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1fr;
  gap: 36px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border-color);
}

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

.footer-brand-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
}

.footer-brand-desc {
  font-size: 13px;
  color: var(--text-body);
  max-width: 320px;
  line-height: 1.6;
}

.footer-nav-col {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-nav-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.footer-nav-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-nav-link {
  font-size: 13px;
  color: var(--text-body);
  transition: color var(--transition-fast);
}

.footer-nav-link:hover {
  color: var(--primary-teal);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 20px;
  font-size: 12px;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 14px;
}

.footer-copyright {
  font-size: 12px;
  color: var(--text-muted);
}

.footer-friend-links {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.friend-links-label {
  color: var(--text-primary);
  font-weight: 600;
}

.friend-link-item {
  color: var(--text-body);
  text-decoration: none;
  font-size: 12px;
  transition: color var(--transition-fast);
}

.friend-link-item:hover {
  color: var(--primary-teal);
}

/* ==========================================================================
   Article & Category Page Specific Styles
   ========================================================================== */

.page-main-wrap {
  padding-top: 36px;
  padding-bottom: 64px;
}

.breadcrumb-nav {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.breadcrumb-separator {
  color: var(--border-dark);
}

.article-container {
  max-width: 800px;
  margin: 0 auto;
}

.article-header {
  margin-bottom: 28px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.article-category-badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--primary-teal);
  background-color: var(--bg-light-teal);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
}

.article-h1 {
  font-size: 30px;
  line-height: 1.35;
  color: var(--text-primary);
  margin-bottom: 14px;
  letter-spacing: -0.4px;
}

.article-summary-text {
  font-size: 16px;
  color: var(--text-body);
  line-height: 1.7;
  margin-bottom: 18px;
}

.article-meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 12px;
  color: var(--text-muted);
}

.article-meta-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* GEO Quick Conclusion Box */
.geo-conclusion-box {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary-teal);
  border-radius: var(--radius-sm);
  padding: 18px 22px;
  margin-bottom: 28px;
}

.geo-conclusion-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--primary-teal);
  margin-bottom: 8px;
}

.geo-conclusion-text {
  font-size: 14px;
  color: var(--text-primary);
  line-height: 1.7;
}

/* Table of Contents */
.article-toc-box {
  background-color: var(--bg-light);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 18px 22px;
  margin-bottom: 32px;
}

.article-toc-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.article-toc-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.article-toc-link {
  font-size: 13px;
  color: var(--text-body);
}

.article-toc-link:hover {
  color: var(--primary-teal);
}

/* Article Prose */
.article-prose {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 40px;
  box-shadow: var(--shadow-sm);
}

.article-prose h2 {
  font-size: 22px;
  color: var(--text-primary);
  margin-top: 36px;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--bg-light);
}

.article-prose h3 {
  font-size: 18px;
  color: var(--text-primary);
  margin-top: 24px;
  margin-bottom: 10px;
}

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

.article-prose ul, .article-prose ol {
  margin-bottom: 18px;
  padding-left: 24px;
}

.article-prose ul {
  list-style: disc;
}

.article-prose ol {
  list-style: decimal;
}

.article-prose li {
  font-size: 15px;
  color: var(--text-body);
  line-height: 1.75;
  margin-bottom: 6px;
}

.article-prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 14px;
}

.article-prose th, .article-prose td {
  border: 1px solid var(--border-color);
  padding: 10px 14px;
  text-align: left;
}

.article-prose th {
  background-color: var(--bg-light);
  color: var(--text-primary);
}

.article-cta-box {
  background-color: var(--bg-light-teal);
  border: 1px solid rgba(40, 124, 130, 0.3);
  border-radius: var(--radius-md);
  padding: 24px;
  text-align: center;
  margin: 36px 0;
}

.article-cta-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.article-cta-desc {
  font-size: 14px;
  color: var(--text-body);
  margin-bottom: 16px;
}

/* Article Navigation */
.article-nav-row {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 36px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.article-nav-item {
  display: flex;
  flex-direction: column;
  max-width: 48%;
}

.article-nav-label {
  font-size: 11px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.article-nav-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary-teal);
}

/* Category Page Intro */
.category-intro-box {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-sm);
}

.category-intro-box h1 {
  font-size: 26px;
  margin-bottom: 12px;
}

.category-intro-box p {
  font-size: 15px;
  color: var(--text-body);
  line-height: 1.7;
}

/* 404 Page */
.page-404-wrap {
  text-align: center;
  padding: 72px 20px;
}

.code-404 {
  font-family: var(--font-mono);
  font-size: 72px;
  font-weight: 800;
  color: var(--primary-teal);
  line-height: 1;
  margin-bottom: 16px;
}

.title-404 {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.desc-404 {
  font-size: 15px;
  color: var(--text-body);
  margin-bottom: 28px;
}

/* ==========================================================================
   Responsive Breakpoints
   Viewports: 375, 390, 430, 768, 1024, 1440
   ========================================================================== */

@media (max-width: 1024px) {
  .site-nav {
    display: none;
  }
  
  .mobile-menu-toggle {
    display: block;
  }
  
  .plan-row-item {
    grid-template-columns: 100px 130px 120px 1fr 130px;
    padding: 16px;
    gap: 12px;
  }

  .direction-index-row {
    grid-template-columns: 110px 140px 1fr 1fr;
    padding: 14px 16px;
  }

  .footer-top {
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
  }
}

@media (max-width: 768px) {
  .section-spacer {
    padding-top: 48px;
    padding-bottom: 48px;
  }

  .hero-visual-title {
    font-size: 28px;
  }

  .hero-subtitle {
    font-size: 14px;
  }

  /* Switch Matrix to 2 cols x 4 rows on mobile */
  .matrix-canvas-wrap {
    display: none;
  }

  .matrix-mobile-grid {
    display: grid;
  }

  .matrix-container {
    padding: 20px 16px;
  }

  /* Direction index on mobile */
  .direction-index-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  /* US Strip on mobile */
  .us-node-strip {
    grid-template-columns: 1fr;
    gap: 14px;
    border-left: none;
    border-top: 4px solid var(--primary-blue);
    padding: 18px;
  }

  .us-right {
    border-left: none;
    border-top: 1px dashed var(--border-color);
    padding-left: 0;
    padding-top: 12px;
  }

  /* Device matrix on mobile */
  .device-matrix-grid {
    grid-template-columns: 1fr 1fr;
  }

  /* Pricing matrix on mobile: Order L3 -> L2 -> L1 -> L4 -> Annual */
  .level-axis-layout {
    grid-template-columns: 1fr;
  }

  .level-axis-rail {
    display: none;
  }

  .level-plan-rows {
    display: flex;
    flex-direction: column;
  }

  /* Reorder on mobile as requested: L3, L2, L1, L4 */
  .plan-row-l3 { order: 1; }
  .plan-row-l2 { order: 2; }
  .plan-row-l1 { order: 3; }
  .plan-row-l4 { order: 4; }

  .plan-row-item {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .plan-fit {
    grid-column: span 2;
  }

  .plan-action {
    grid-column: span 2;
    text-align: left;
  }

  .annual-plan-strip {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    padding: 18px;
  }

  .annual-fit {
    grid-column: span 2;
  }

  .annual-action {
    grid-column: span 2;
  }

  /* Troubleshoot steps on mobile */
  .troubleshoot-flow {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Knowledge index on mobile */
  .knowledge-matrix-header {
    display: none;
  }

  .knowledge-matrix-row {
    grid-template-columns: 1fr;
    gap: 6px;
    padding: 14px 18px;
  }

  .km-action {
    text-align: left;
    margin-top: 4px;
  }

  /* Review card on mobile */
  .review-highlight-card {
    grid-template-columns: 1fr;
    padding: 20px;
    gap: 20px;
  }

  /* Article prose on mobile */
  .article-prose {
    padding: 24px 18px;
  }

  .article-h1 {
    font-size: 24px;
  }

  /* Footer on mobile */
  .footer-top {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 430px) {
  .hero-visual-title {
    font-size: 24px;
  }

  .device-matrix-grid {
    grid-template-columns: 1fr;
  }

  .troubleshoot-flow {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn {
    width: 100%;
  }

  .plan-row-item {
    grid-template-columns: 1fr;
  }

  .plan-fit, .plan-action {
    grid-column: span 1;
  }

  .annual-plan-strip {
    grid-template-columns: 1fr;
  }

  .annual-fit, .annual-action {
    grid-column: span 1;
  }
}

/* ==========================================================================
   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;
  }
  .btn:hover .btn-arrow {
    transform: none;
  }
  .matrix-item:hover {
    transform: none;
  }
}