/* ==========================================================================
   DOVE加速 官方推广与技术评测 - 全局样式表
   DESIGN: A calm 3D route tunnel.
   Colors:
     - white: #FFFFFF
     - deep teal: #1E5051
     - soft aqua: #A9D4CD
     - warm gray: #EDEBE6
   Typography:
     - Headings: Bold Chinese system sans-serif
     - Body: Regular sans-serif (18px)
     - Small route IDs: Monospace
     - H1: 52px desktop / 35px mobile
   ========================================================================== */

:root {
  --color-white: #FFFFFF;
  --color-deep-teal: #1E5051;
  --color-deep-teal-dark: #143839;
  --color-deep-teal-light: #286869;
  --color-soft-aqua: #A9D4CD;
  --color-soft-aqua-light: #EBF5F3;
  --color-soft-aqua-border: #8ec3ba;
  --color-warm-gray: #EDEBE6;
  --color-warm-gray-light: #F7F6F3;
  --color-warm-gray-dark: #DCD8D0;
  --color-text-main: #142829;
  --color-text-body: #243E3F;
  --color-text-muted: #566D6E;
  
  /* Typography */
  --font-heading: system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei UI", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  /* Layout */
  --container-max: 1220px;
  --container-narrow: 880px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-pill: 9999px;
  --shadow-subtle: 0 4px 16px rgba(30, 80, 81, 0.06);
  --shadow-hover: 0 8px 24px rgba(30, 80, 81, 0.12);
  --transition-normal: 0.25s ease;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--color-white);
  color: var(--color-text-body);
}

body {
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 1.75;
  color: var(--color-text-body);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--color-deep-teal);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

h1 {
  font-size: 52px;
  line-height: 1.2;
}

h2 {
  font-size: 34px;
  margin-bottom: 0.8rem;
}

h3 {
  font-size: 22px;
  margin-bottom: 0.6rem;
}

p {
  margin-bottom: 1.2rem;
}

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

a {
  color: var(--color-deep-teal);
  text-decoration: none;
  transition: color var(--transition-normal);
}

a:hover {
  color: var(--color-deep-teal-light);
}

ul, ol {
  margin-bottom: 1.2rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.4rem;
}

code, .route-id {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  padding: 0.15em 0.45em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-warm-gray-dark);
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.container-narrow {
  max-width: var(--container-narrow);
}

/* Badges & Tags */
.badge-mono {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.05em;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  border: 1px solid var(--color-soft-aqua);
  text-transform: uppercase;
}

.badge-featured {
  background-color: var(--color-deep-teal);
  color: var(--color-white);
  border: 1px solid var(--color-deep-teal);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-size: 17px;
  font-weight: 600;
  padding: 13px 28px;
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  cursor: pointer;
  text-align: center;
  transition: all var(--transition-normal);
}

.btn-primary {
  background-color: var(--color-deep-teal);
  color: var(--color-white);
  border-color: var(--color-deep-teal);
  box-shadow: 0 4px 12px rgba(30, 80, 81, 0.2);
}

.btn-primary:hover {
  background-color: var(--color-deep-teal-light);
  border-color: var(--color-deep-teal-light);
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(30, 80, 81, 0.28);
}

.btn-secondary {
  background-color: var(--color-white);
  color: var(--color-deep-teal);
  border-color: var(--color-soft-aqua-border);
}

.btn-secondary:hover {
  background-color: var(--color-soft-aqua-light);
  border-color: var(--color-deep-teal);
  color: var(--color-deep-teal);
}

.btn-sm {
  font-size: 15px;
  padding: 8px 18px;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-warm-gray);
  padding: 14px 0;
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-deep-teal);
}

.brand-logo svg {
  width: 34px;
  height: 34px;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 2px 7px;
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-soft-aqua);
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-link {
  font-family: var(--font-heading);
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text-body);
}

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

.header-cta-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--color-warm-gray-dark);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep-teal);
}

/* Mobile Drawer */
.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 65px;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--color-white);
  padding: 24px;
  z-index: 999;
  border-top: 1px solid var(--color-warm-gray);
  overflow-y: auto;
}

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

.mobile-nav-links {
  list-style: none;
  padding: 0;
  margin: 0 0 24px 0;
}

.mobile-nav-links li {
  border-bottom: 1px solid var(--color-warm-gray);
}

.mobile-nav-links a {
  display: block;
  padding: 14px 0;
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text-main);
}

/* ==========================================================================
   Hero Section & Calm 3D Route Tunnel
   ========================================================================== */
.hero-section {
  padding: 60px 0 80px 0;
  background: linear-gradient(180deg, var(--color-white) 0%, var(--color-warm-gray-light) 100%);
  border-bottom: 1px solid var(--color-warm-gray);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.95fr;
  gap: 48px;
  align-items: center;
}

.hero-content {
  max-width: 600px;
}

.hero-meta {
  margin-bottom: 18px;
}

.hero-title {
  font-size: 52px;
  margin-bottom: 20px;
  color: var(--color-deep-teal);
  line-height: 1.18;
}

.hero-intro {
  font-size: 18px;
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: 28px;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-bottom: 32px;
}

.hero-trust-points {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  font-size: 14px;
  color: var(--color-text-muted);
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-heading);
}

.trust-item svg {
  color: var(--color-deep-teal);
}

/* 3D Route Tunnel Dashboard */
.hero-dashboard-container {
  position: relative;
  background-color: var(--color-white);
  border: 1px solid var(--color-soft-aqua);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: 0 12px 36px rgba(30, 80, 81, 0.08);
}

.dashboard-header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 14px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--color-warm-gray);
}

.tunnel-viewport {
  position: relative;
  width: 100%;
  height: 380px;
  perspective: 800px;
  overflow: hidden;
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, #184142 0%, var(--color-deep-teal) 60%, #153c3d 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

/* 3D frames stage */
.tunnel-stage {
  position: absolute;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Perspective connecting lines (SVG) */
.tunnel-svg-guide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

/* Moving wireframes */
.tunnel-frame {
  position: absolute;
  width: 280px;
  height: 200px;
  border: 1.5px solid rgba(169, 212, 205, 0.45);
  border-radius: 8px;
  box-shadow: inset 0 0 14px rgba(169, 212, 205, 0.12);
  transform-style: preserve-3d;
  animation: tunnelAdvance 12s linear infinite;
  pointer-events: none;
}

.tunnel-frame:nth-child(1) { animation-delay: 0s; }
.tunnel-frame:nth-child(2) { animation-delay: -3s; }
.tunnel-frame:nth-child(3) { animation-delay: -6s; }
.tunnel-frame:nth-child(4) { animation-delay: -9s; }

@keyframes tunnelAdvance {
  0% {
    transform: translateZ(-500px) scale(0.35);
    opacity: 0.1;
    border-color: rgba(169, 212, 205, 0.15);
  }
  20% {
    opacity: 0.6;
  }
  75% {
    opacity: 0.85;
    border-color: rgba(169, 212, 205, 0.7);
  }
  100% {
    transform: translateZ(240px) scale(1.4);
    opacity: 0;
    border-color: rgba(169, 212, 205, 0);
  }
}

/* Fixed readable layer */
.tunnel-fixed-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  padding: 16px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  pointer-events: none;
  z-index: 10;
}

.tunnel-route-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: rgba(20, 56, 57, 0.88);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--color-soft-aqua);
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  color: var(--color-white);
  font-family: var(--font-mono);
  font-size: 13px;
  align-self: flex-start;
}

.route-indicator-dot {
  width: 8px;
  height: 8px;
  background-color: var(--color-soft-aqua);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--color-soft-aqua);
}

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

.tunnel-node-card {
  background-color: rgba(255, 255, 255, 0.94);
  border: 1px solid var(--color-warm-gray);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  color: var(--color-deep-teal);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

.tunnel-node-card .node-label {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--color-deep-teal);
}

.tunnel-node-card .node-status {
  font-size: 12px;
  color: var(--color-text-muted);
  margin-top: 2px;
}

/* Static fallback for reduced motion */
@media (prefers-reduced-motion: reduce) {
  .tunnel-frame {
    animation: none !important;
    transform: translateZ(-150px) scale(0.8) !important;
    opacity: 0.7 !important;
  }
}

/* Paused when offscreen */
.tunnel-paused .tunnel-frame {
  animation-play-state: paused !important;
}

/* ==========================================================================
   Advantages Section: 1 Wide Feature Story + 2 Compact Explanations
   ========================================================================== */
.advantages-section {
  padding: 80px 0;
  background-color: var(--color-white);
}

.section-title-wrap {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 48px auto;
}

.section-subtitle {
  font-size: 18px;
  color: var(--color-text-muted);
}

.advantages-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

/* 1 Wide Feature Story */
.wide-feature-story {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 36px;
  background-color: var(--color-warm-gray-light);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 40px;
  align-items: center;
}

.wide-feature-content h3 {
  font-size: 28px;
  margin-bottom: 16px;
  color: var(--color-deep-teal);
}

.wide-feature-content p {
  color: var(--color-text-body);
  line-height: 1.8;
}

.wide-feature-visual {
  background-color: var(--color-white);
  border: 1px solid var(--color-soft-aqua);
  border-radius: var(--radius-md);
  padding: 24px;
}

.feature-spec-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.feature-spec-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--color-warm-gray);
  font-size: 16px;
}

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

.spec-icon {
  color: var(--color-deep-teal);
  flex-shrink: 0;
  margin-top: 3px;
}

/* 2 Compact Explanations */
.compact-advantages-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.compact-advantage-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition-normal);
}

.compact-advantage-card:hover {
  border-color: var(--color-soft-aqua-border);
  box-shadow: var(--shadow-subtle);
  transform: translateY(-2px);
}

.compact-card-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.compact-card-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background-color: var(--color-warm-gray);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-deep-teal);
  flex-shrink: 0;
}

.compact-advantage-card h3 {
  font-size: 22px;
  margin-bottom: 0;
}

.compact-advantage-card p {
  font-size: 16px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

/* ==========================================================================
   Global Nodes: Ordered Region List
   ========================================================================== */
.nodes-section {
  padding: 80px 0;
  background-color: var(--color-warm-gray-light);
  border-top: 1px solid var(--color-warm-gray);
  border-bottom: 1px solid var(--color-warm-gray);
}

.nodes-ordered-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.node-list-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-md);
  padding: 22px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: all var(--transition-normal);
}

.node-list-item:hover {
  border-color: var(--color-deep-teal);
  box-shadow: var(--shadow-subtle);
}

.node-rank-num {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  width: 38px;
  height: 38px;
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  border: 1px solid var(--color-soft-aqua);
}

.node-item-body {
  flex-grow: 1;
}

.node-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.node-region-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-deep-teal);
}

.node-scenario-desc {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.6;
}

.editorial-note-box {
  margin-top: 32px;
  background-color: var(--color-white);
  border: 1px dashed var(--color-soft-aqua-border);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  font-size: 14px;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: 12px;
}

/* ==========================================================================
   AI & Streaming Full-Width Distinct Sections
   ========================================================================== */
.ai-section {
  padding: 85px 0;
  background: linear-gradient(180deg, #184142 0%, var(--color-deep-teal) 100%);
  color: var(--color-white);
}

.ai-section h2, .ai-section h3 {
  color: var(--color-white);
}

.ai-section .section-subtitle {
  color: var(--color-soft-aqua);
}

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

.ai-card {
  background-color: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(169, 212, 205, 0.35);
  border-radius: var(--radius-lg);
  padding: 26px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: all var(--transition-normal);
}

.ai-card:hover {
  background-color: rgba(255, 255, 255, 0.14);
  border-color: var(--color-soft-aqua);
  transform: translateY(-3px);
}

.ai-card-tag {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-soft-aqua);
  margin-bottom: 8px;
  display: block;
}

.ai-card h3 {
  font-size: 20px;
  margin-bottom: 10px;
}

.ai-card p {
  font-size: 15px;
  color: #D3E6E4;
  line-height: 1.65;
  margin-bottom: 0;
}

/* Streaming Distinct Section */
.streaming-section {
  padding: 85px 0;
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-warm-gray);
}

.streaming-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}

.streaming-card {
  background-color: var(--color-warm-gray-light);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
  text-align: center;
  transition: all var(--transition-normal);
}

.streaming-card:hover {
  border-color: var(--color-deep-teal);
  box-shadow: var(--shadow-subtle);
  transform: translateY(-2px);
}

.streaming-card-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 14px auto;
  border-radius: var(--radius-md);
  background-color: var(--color-white);
  border: 1px solid var(--color-soft-aqua);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-deep-teal);
}

.streaming-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.streaming-card p {
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 0;
}

/* ==========================================================================
   Pricing Section: 4-5 Tiers with exactly ONE "推荐套餐"
   ========================================================================== */
.pricing-section {
  padding: 85px 0;
  background-color: var(--color-warm-gray-light);
}

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

.pricing-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: all var(--transition-normal);
}

.pricing-card:hover {
  box-shadow: var(--shadow-hover);
}

/* Exactly ONE Recommended Tier */
.pricing-card.is-recommended {
  border: 2px solid var(--color-deep-teal);
  box-shadow: 0 8px 30px rgba(30, 80, 81, 0.14);
  transform: scale(1.02);
  z-index: 2;
}

.recommended-pill {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--color-deep-teal);
  color: var(--color-white);
  font-family: var(--font-heading);
  font-size: 13px;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: var(--radius-pill);
  box-shadow: 0 2px 8px rgba(30, 80, 81, 0.25);
}

.pricing-header {
  text-align: center;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--color-warm-gray);
  margin-bottom: 20px;
}

.pricing-tier-name {
  font-size: 22px;
  margin-bottom: 6px;
}

.pricing-price-wrap {
  margin: 14px 0 6px 0;
}

.price-currency {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-deep-teal);
}

.price-amount {
  font-size: 42px;
  font-weight: 800;
  font-family: var(--font-heading);
  color: var(--color-deep-teal);
  line-height: 1;
}

.price-period {
  font-size: 14px;
  color: var(--color-text-muted);
}

.pricing-tier-desc {
  font-size: 14px;
  color: var(--color-text-muted);
}

.pricing-features-list {
  list-style: none;
  padding: 0;
  margin: 0 0 24px 0;
  flex-grow: 1;
}

.pricing-feature-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  padding: 8px 0;
  color: var(--color-text-body);
}

.feature-check {
  color: var(--color-deep-teal);
  flex-shrink: 0;
}

.pricing-cta-wrap {
  margin-top: auto;
}

.pricing-disclaimer {
  text-align: center;
  margin-top: 32px;
  font-size: 14px;
  color: var(--color-text-muted);
}

/* ==========================================================================
   Nine Article Cards Section (3 desktop / 2 tablet / 1 mobile)
   ========================================================================== */
.articles-section {
  padding: 85px 0;
  background-color: var(--color-white);
  border-top: 1px solid var(--color-warm-gray);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.article-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
}

.article-card:hover {
  border-color: var(--color-deep-teal);
  box-shadow: var(--shadow-subtle);
  transform: translateY(-2px);
}

.article-card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.article-card-tag {
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
}

.article-card-date {
  font-size: 13px;
  color: var(--color-text-muted);
}

.article-card-title {
  font-size: 20px;
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card-title a {
  color: var(--color-deep-teal);
}

.article-card-title a:hover {
  color: var(--color-deep-teal-light);
}

.article-card-desc {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.65;
  margin-bottom: 18px;
  flex-grow: 1;
}

.article-card-footer {
  margin-top: auto;
  border-top: 1px solid var(--color-warm-gray);
  padding-top: 14px;
}

.article-read-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-deep-teal);
}

/* ==========================================================================
   Testimonials: 3-6 Authentic or Marked-Sample Testimonials
   ========================================================================== */
.testimonials-section {
  padding: 80px 0;
  background-color: var(--color-warm-gray-light);
  border-top: 1px solid var(--color-warm-gray);
}

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

.testimonial-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
}

.sample-badge {
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 2px 8px;
  background-color: var(--color-warm-gray);
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: 12px;
  align-self: flex-start;
}

.testimonial-quote {
  font-size: 16px;
  color: var(--color-text-body);
  line-height: 1.7;
  margin-bottom: 20px;
  flex-grow: 1;
  font-style: normal;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--color-warm-gray);
  padding-top: 14px;
}

.author-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 14px;
}

.author-info h4 {
  font-size: 15px;
  margin-bottom: 2px;
}

.author-info p {
  font-size: 13px;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

/* ==========================================================================
   FAQ Section
   ========================================================================== */
.faq-section {
  padding: 85px 0;
  background-color: var(--color-white);
  border-top: 1px solid var(--color-warm-gray);
}

.faq-list {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--color-warm-gray-dark);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  transition: all var(--transition-normal);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  background-color: var(--color-white);
  border: none;
  cursor: pointer;
  text-align: left;
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 600;
  color: var(--color-deep-teal);
  transition: background-color var(--transition-normal);
}

.faq-question:hover {
  background-color: var(--color-warm-gray-light);
}

.faq-toggle-icon {
  font-size: 20px;
  color: var(--color-deep-teal);
  transition: transform var(--transition-normal);
}

.faq-item.is-open .faq-toggle-icon {
  transform: rotate(45deg);
}

.faq-answer {
  display: none;
  padding: 0 24px 22px 24px;
  font-size: 16px;
  color: var(--color-text-body);
  line-height: 1.75;
  background-color: var(--color-white);
}

.faq-item.is-open .faq-answer {
  display: block;
}

/* ==========================================================================
   Footer & PBN Dofollow Matrix
   ========================================================================== */
.site-footer {
  background-color: var(--color-warm-gray-light);
  border-top: 2px solid var(--color-warm-gray);
  padding: 60px 0 30px 0;
}

.footer-nav-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand-col p {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.footer-col-title {
  font-size: 17px;
  margin-bottom: 16px;
  color: var(--color-deep-teal);
}

.footer-links-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-links-list li {
  margin-bottom: 10px;
}

.footer-links-list a {
  font-size: 15px;
  color: var(--color-text-body);
}

.footer-links-list a:hover {
  color: var(--color-deep-teal);
}

/* PBN matrix section */
.footer-pbn-section {
  border-top: 1px solid var(--color-warm-gray-dark);
  border-bottom: 1px solid var(--color-warm-gray-dark);
  padding: 24px 0;
  margin-bottom: 28px;
  text-align: center;
}

.pbn-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-deep-teal);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pbn-links-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 24px;
}

.pbn-link {
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-deep-teal);
  padding: 6px 14px;
  background-color: var(--color-white);
  border: 1px solid var(--color-soft-aqua);
  border-radius: var(--radius-sm);
  transition: all var(--transition-normal);
}

.pbn-link:hover {
  background-color: var(--color-deep-teal);
  color: var(--color-white);
}

.footer-bottom {
  text-align: center;
  font-size: 14px;
  color: var(--color-text-muted);
}

/* ==========================================================================
   Article & Content Subpage Specific Styles
   ========================================================================== */
.subpage-hero {
  padding: 50px 0 40px 0;
  background: linear-gradient(180deg, var(--color-white) 0%, var(--color-warm-gray-light) 100%);
  border-bottom: 1px solid var(--color-warm-gray);
}

.breadcrumb-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-muted);
  margin-bottom: 18px;
}

.breadcrumb-nav a {
  color: var(--color-deep-teal);
}

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

.subpage-h1 {
  font-size: 40px;
  line-height: 1.25;
  margin-bottom: 16px;
  color: var(--color-deep-teal);
}

.subpage-lead {
  font-size: 18px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.article-content-layout {
  padding: 60px 0 80px 0;
}

.article-body {
  font-size: 18px;
  line-height: 1.8;
  color: var(--color-text-body);
}

.article-body h2 {
  font-size: 28px;
  margin-top: 48px;
  margin-bottom: 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-warm-gray);
}

.article-body h3 {
  font-size: 22px;
  margin-top: 32px;
  margin-bottom: 14px;
}

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

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

.article-body strong {
  color: var(--color-deep-teal);
}

.callout-box {
  background-color: var(--color-warm-gray-light);
  border-left: 4px solid var(--color-deep-teal);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 20px 24px;
  margin: 28px 0;
}

.callout-box p:last-child {
  margin-bottom: 0;
}

.comparison-table-wrap {
  overflow-x: auto;
  margin: 32px 0;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 16px;
  text-align: left;
}

.data-table th, .data-table td {
  padding: 14px 18px;
  border: 1px solid var(--color-warm-gray-dark);
}

.data-table th {
  background-color: var(--color-warm-gray);
  color: var(--color-deep-teal);
  font-weight: 700;
}

.data-table tr:nth-child(even) td {
  background-color: var(--color-warm-gray-light);
}

.related-articles-section {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 2px solid var(--color-warm-gray);
}

.related-articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 20px;
}

/* ==========================================================================
   Responsive Breakpoints: 375, 390, 430, 768, 1024, 1440px
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .wide-feature-story {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .pricing-card.is-recommended {
    transform: none;
  }

  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .ai-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .streaming-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-nav-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 17px;
  }

  h1 {
    font-size: 35px;
    line-height: 1.25;
  }

  h2 {
    font-size: 26px;
  }

  .desktop-nav, .header-cta-group {
    display: none;
  }

  .mobile-menu-toggle {
    display: block;
  }

  .compact-advantages-row {
    grid-template-columns: 1fr;
  }

  .nodes-ordered-list {
    grid-template-columns: 1fr;
  }

  .ai-grid {
    grid-template-columns: 1fr;
  }

  .streaming-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .pricing-grid {
    grid-template-columns: 1fr;
  }

  .articles-grid {
    grid-template-columns: 1fr;
  }

  .testimonials-grid {
    grid-template-columns: 1fr;
  }

  .footer-nav-grid {
    grid-template-columns: 1fr;
  }

  .subpage-h1 {
    font-size: 30px;
  }

  .related-articles-grid {
    grid-template-columns: 1fr;
  }

  /* Tunnel reduced depth on phones */
  .tunnel-viewport {
    height: 300px;
    perspective: 500px;
  }

  .tunnel-frame {
    width: 210px;
    height: 150px;
  }

  .tunnel-nodes-display {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 430px) {
  .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .hero-cta-group .btn {
    width: 100%;
  }

  .streaming-grid {
    grid-template-columns: 1fr;
  }

  .hero-dashboard-container {
    padding: 16px;
  }
}