/* 
  Taishan (泰山) - Custom CSS Design System
  Theme: White-space-led vermilion geometry
  Colors:
    - White: #FFFFFF
    - Ink: #282D30
    - Muted Vermilion: #B76655
    - Pale Warm Gray: #F3EFEA
*/

:root {
  --color-white: #FFFFFF;
  --color-ink: #282D30;
  --color-vermilion: #B76655;
  --color-warm-gray: #F3EFEA;
  
  --color-ink-muted: #596166;
  --color-ink-light: #808B91;
  --color-border: rgba(40, 45, 48, 0.12);
  --color-border-strong: rgba(40, 45, 48, 0.28);
  --color-vermilion-light: rgba(183, 102, 85, 0.08);
  --color-vermilion-glow: rgba(183, 102, 85, 0.18);

  --font-heading: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --font-mono: SFMono-Regular, Consolas, "Liberation Mono", Menlo, Courier, monospace;

  --max-width: 1240px;
  --header-height: 72px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
}

/* Base Reset & Typography */
*, *::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-ink);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-ink);
  background-color: var(--color-white);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-ink);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 38px; /* Mobile 38px */
  margin-bottom: 1rem;
}

@media (min-width: 1024px) {
  h1 {
    font-size: 64px; /* Desktop 64px */
    line-height: 1.15;
  }
}

h2 {
  font-size: 28px;
  margin-bottom: 0.75rem;
}

@media (min-width: 768px) {
  h2 {
    font-size: 36px;
  }
}

h3 {
  font-size: 20px;
  margin-bottom: 0.5rem;
}

@media (min-width: 768px) {
  h3 {
    font-size: 22px;
  }
}

p {
  margin-bottom: 1rem;
  color: var(--color-ink-muted);
}

a {
  color: var(--color-vermilion);
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

a:hover {
  opacity: 0.85;
}

/* Monospace restricted strictly to small region tags */
.region-tag, .tech-code {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

/* Container & Layout Utilities */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

@media (min-width: 768px) {
  .container {
    padding: 0 2rem;
  }
}

.section {
  padding: 4rem 0;
}

@media (min-width: 1024px) {
  .section {
    padding: 6rem 0;
  }
}

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

.section-header {
  max-width: 760px;
  margin: 0 auto 3rem auto;
  text-align: center;
}

.section-header p {
  font-size: 1.1rem;
}

.badge-tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background-color: var(--color-vermilion-light);
  color: var(--color-vermilion);
  border: 1px solid rgba(183, 102, 85, 0.25);
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all 0.25s ease;
  cursor: pointer;
  text-decoration: none;
  border: 2px solid transparent;
}

.btn-primary {
  background-color: var(--color-vermilion);
  color: var(--color-white);
  box-shadow: 0 4px 14px rgba(183, 102, 85, 0.25);
}

.btn-primary:hover {
  background-color: #A25545;
  color: var(--color-white);
  box-shadow: 0 6px 20px rgba(183, 102, 85, 0.35);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-ink);
  border-color: var(--color-ink);
}

.btn-secondary:hover {
  background-color: var(--color-ink);
  color: var(--color-white);
  transform: translateY(-1px);
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
}

/* Header & Navigation */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
  display: flex;
  align-items: center;
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--color-ink);
  text-decoration: none;
  letter-spacing: -0.03em;
}

.logo-symbol {
  width: 32px;
  height: 32px;
  background-color: var(--color-vermilion);
  clip-path: polygon(50% 0%, 100% 100%, 0% 100%);
  display: inline-block;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-link {
  color: var(--color-ink);
  font-weight: 500;
  font-size: 0.95rem;
}

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

.nav-cta {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Mobile Nav Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--color-ink);
}

.mobile-toggle svg {
  width: 28px;
  height: 28px;
  display: block;
}

@media (max-width: 991px) {
  .mobile-toggle {
    display: block;
  }
  
  .nav-menu {
    position: absolute;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background-color: var(--color-white);
    flex-direction: column;
    padding: 1.5rem 2rem;
    gap: 1.25rem;
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    display: none;
  }

  .nav-menu.active {
    display: flex;
  }

  .nav-cta {
    display: none;
  }

  .nav-menu .mobile-cta-item {
    width: 100%;
    margin-top: 0.5rem;
  }

  .nav-menu .mobile-cta-item .btn {
    width: 100%;
  }
}

/* Hero Section */
.hero {
  padding: 4rem 0 5rem 0;
  overflow: hidden;
  background-color: var(--color-white);
}

@media (min-width: 1024px) {
  .hero {
    padding: 5rem 0 7rem 0;
  }
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}

@media (min-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 4rem;
  }
}

.hero-title {
  color: var(--color-ink);
  margin-bottom: 1.5rem;
}

.hero-subtitle {
  font-size: 1.15rem;
  line-height: 1.7;
  color: var(--color-ink-muted);
  margin-bottom: 2rem;
  max-width: 600px;
}

/* Hero Geometric Dashboard (Right Side) */
.hero-dashboard {
  background-color: var(--color-warm-gray);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  position: relative;
  box-shadow: 0 12px 32px rgba(40, 45, 48, 0.04);
}

.dashboard-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 1rem;
  margin-bottom: 1.5rem;
}

.dashboard-title {
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-ink);
}

.dashboard-matrix {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  position: relative;
}

.matrix-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  position: relative;
  z-index: 2;
  transition: border-color 0.2s ease;
}

.matrix-card:hover {
  border-color: var(--color-vermilion);
}

.matrix-node-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}

.matrix-node-name {
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-ink);
}

.matrix-node-tag {
  color: var(--color-vermilion);
  background: var(--color-vermilion-light);
  padding: 0.15rem 0.4rem;
  border-radius: var(--radius-sm);
}

.matrix-desc {
  font-size: 0.85rem;
  color: var(--color-ink-muted);
  margin-bottom: 0;
}

/* Interlocking Animated Vermilion SVG Line */
.route-svg-container {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

.animated-route-line {
  stroke: var(--color-vermilion);
  stroke-width: 2.5;
  stroke-dasharray: 8 6;
  fill: none;
  animation: routeDash 20s linear infinite;
}

@keyframes routeDash {
  to {
    stroke-dashoffset: -200;
  }
}

@media (prefers-reduced-motion: reduce) {
  .animated-route-line {
    animation: none;
  }
}

/* Three Advantages Section (Broad color blocks with geometric shapes) */
.advantages-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .advantages-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.advantage-card {
  padding: 2.5rem 2rem;
  border-radius: var(--radius-lg);
  position: relative;
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  display: flex;
  flex-direction: column;
}

.advantage-card:hover {
  transform: translateY(-4px);
}

/* Shape 1: Warm Gray Rect Block */
.advantage-card-1 {
  background-color: var(--color-warm-gray);
  border: 1px solid var(--color-border);
}

/* Shape 2: Ink Dark Accent Block */
.advantage-card-2 {
  background-color: var(--color-ink);
  color: var(--color-white);
}

.advantage-card-2 h3, .advantage-card-2 p {
  color: var(--color-white);
}

.advantage-card-2 p {
  opacity: 0.85;
}

/* Shape 3: White Vermilion Border Block */
.advantage-card-3 {
  background-color: var(--color-white);
  border: 2px solid var(--color-vermilion);
}

.advantage-shape-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.geo-triangle {
  width: 0;
  height: 0;
  border-left: 24px solid transparent;
  border-right: 24px solid transparent;
  border-bottom: 42px solid var(--color-vermilion);
}

.geo-square {
  width: 40px;
  height: 40px;
  background-color: var(--color-vermilion);
  transform: rotate(45deg);
}

.geo-circle {
  width: 44px;
  height: 44px;
  background-color: var(--color-vermilion);
  border-radius: 50%;
}

.advantage-title {
  font-size: 1.4rem;
  margin-bottom: 0.8rem;
}

.advantage-body {
  font-size: 0.95rem;
  line-height: 1.65;
  margin: 0;
}

/* Geographic Matrix Nodes Section */
.nodes-matrix {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .nodes-matrix {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .nodes-matrix {
    grid-template-columns: repeat(4, 1fr);
  }
}

.node-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.25s ease;
}

.node-item:hover {
  border-color: var(--color-vermilion);
  box-shadow: 0 8px 24px rgba(40, 45, 48, 0.06);
}

.node-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.node-name {
  font-size: 1.25rem;
  font-weight: 700;
}

.node-region-code {
  background-color: var(--color-warm-gray);
  color: var(--color-ink);
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

.node-desc {
  font-size: 0.9rem;
  color: var(--color-ink-muted);
  margin-bottom: 1.25rem;
}

.node-features {
  list-style: none;
  border-top: 1px dashed var(--color-border);
  padding-top: 1rem;
}

.node-features li {
  font-size: 0.85rem;
  color: var(--color-ink-muted);
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.node-features li::before {
  content: "";
  width: 6px;
  height: 6px;
  background-color: var(--color-vermilion);
  border-radius: 50%;
  display: inline-block;
}

/* AI & Streaming Full-Width Stories */
.story-section {
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

.story-block {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem 1.5rem;
}

@media (min-width: 768px) {
  .story-block {
    padding: 3.5rem 3rem;
  }
}

.story-header-flex {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--color-warm-gray);
  padding-bottom: 1.5rem;
}

@media (min-width: 768px) {
  .story-header-flex {
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-end;
  }
}

.story-tags-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
}

@media (min-width: 640px) {
  .story-tags-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1024px) {
  .story-tags-grid {
    grid-template-columns: repeat(6, 1fr);
  }
}

.story-app-card {
  background-color: var(--color-warm-gray);
  border-radius: var(--radius-md);
  padding: 1.25rem 1rem;
  border: 1px solid var(--color-border);
  transition: transform 0.2s ease;
}

.story-app-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-vermilion);
}

.story-app-name {
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-ink);
  margin-bottom: 0.3rem;
}

.story-app-desc {
  font-size: 0.82rem;
  color: var(--color-ink-muted);
  line-height: 1.4;
  margin: 0;
}

/* Pricing Comparison Tiers */
.pricing-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .pricing-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.pricing-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.pricing-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(40, 45, 48, 0.08);
}

/* Recommended Plan Highlight */
.pricing-card.featured {
  border: 2px solid var(--color-vermilion);
  box-shadow: 0 12px 36px var(--color-vermilion-glow);
}

.featured-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--color-vermilion);
  color: var(--color-white);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.25rem 1rem;
  border-radius: 100px;
  white-space: nowrap;
  letter-spacing: 0.03em;
}

.pricing-plan-name {
  font-size: 1.35rem;
  margin-bottom: 0.5rem;
}

.pricing-placeholder-box {
  background-color: var(--color-warm-gray);
  border: 1px dashed var(--color-ink-light);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  font-size: 0.85rem;
  color: var(--color-ink-muted);
  margin-bottom: 1.25rem;
  text-align: center;
}

.pricing-price-box {
  display: flex;
  align-items: baseline;
  gap: 0.2rem;
  margin: 0.5rem 0 0.25rem 0;
}

.pricing-currency {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-vermilion);
}

.pricing-amount {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--color-ink);
  line-height: 1;
  letter-spacing: -0.03em;
}

.pricing-period {
  font-size: 0.9rem;
  color: var(--color-ink-muted);
  font-weight: 500;
}

.pricing-sub-info {
  font-size: 0.85rem;
  color: var(--color-vermilion);
  background-color: var(--color-vermilion-light);
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1.25rem;
  display: inline-block;
  font-weight: 600;
}

.pricing-features {
  list-style: none;
  margin-bottom: 2rem;
}

.pricing-features li {
  font-size: 0.9rem;
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(40, 45, 48, 0.06);
  color: var(--color-ink-muted);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.pricing-features li svg {
  width: 16px;
  height: 16px;
  color: var(--color-vermilion);
  flex-shrink: 0;
}

/* Testimonials Section */
.testimonials-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .testimonials-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.testimonial-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.testimonial-text {
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--color-ink);
  margin-bottom: 1.5rem;
  font-style: normal;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.author-avatar-geo {
  width: 36px;
  height: 36px;
  background-color: var(--color-vermilion-light);
  color: var(--color-vermilion);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
}

.author-info {
  display: flex;
  flex-direction: column;
}

.author-name {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--color-ink);
}

.author-role {
  font-size: 0.8rem;
  color: var(--color-ink-light);
}

.sample-tag {
  display: inline-block;
  font-size: 0.75rem;
  color: var(--color-ink-light);
  margin-top: 0.25rem;
}

/* Nine SEO Cards (below pricing: 3 desktop / 2 tablet / 1 mobile columns) */
.seo-articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .seo-articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .seo-articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.seo-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color 0.25s ease, transform 0.25s ease;
  position: relative;
}

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

.seo-card-number {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 800;
  color: var(--color-vermilion);
  line-height: 1;
  margin-bottom: 0.75rem;
  opacity: 0.85;
}

.seo-card-title {
  font-size: 1.15rem;
  margin-bottom: 0.6rem;
  line-height: 1.35;
}

.seo-card-title a {
  color: var(--color-ink);
}

.seo-card-title a:hover {
  color: var(--color-vermilion);
}

.seo-card-excerpt {
  font-size: 0.88rem;
  color: var(--color-ink-muted);
  line-height: 1.55;
  margin-bottom: 1.25rem;
}

.seo-card-link {
  font-size: 0.88rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

/* FAQ Accordion Section */
.faq-list {
  max-width: 840px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item[open] {
  border-color: var(--color-vermilion);
}

.faq-summary {
  padding: 1.25rem 1.5rem;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--color-ink);
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-summary::-webkit-details-marker {
  display: none;
}

.faq-summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--color-vermilion);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  content: "−";
}

.faq-content {
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 0.95rem;
  color: var(--color-ink-muted);
  line-height: 1.65;
  border-top: 1px solid var(--color-warm-gray);
  padding-top: 1rem;
}

/* Article Specific Styling */
.article-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 3rem 1.25rem 5rem 1.25rem;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.88rem;
  color: var(--color-ink-light);
  margin-bottom: 2rem;
}

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

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

.breadcrumb-separator {
  color: var(--color-ink-light);
}

.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 2rem;
}

.article-meta {
  display: flex;
  gap: 1.5rem;
  font-size: 0.88rem;
  color: var(--color-ink-light);
  margin-top: 1rem;
}

.article-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--color-ink);
}

.article-content h2 {
  font-size: 1.75rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-warm-gray);
}

.article-content h3 {
  font-size: 1.3rem;
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
}

.article-content p {
  margin-bottom: 1.25rem;
}

.article-content ul, .article-content ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-content blockquote {
  border-left: 4px solid var(--color-vermilion);
  background-color: var(--color-warm-gray);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-style: normal;
}

.article-cta-box {
  background-color: var(--color-warm-gray);
  border: 1px solid var(--color-vermilion);
  border-radius: var(--radius-lg);
  padding: 2rem;
  margin: 3rem 0;
  text-align: center;
}

.article-related {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--color-border);
}

.article-related-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 1rem;
}

@media (min-width: 640px) {
  .article-related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Footer Section */
.footer {
  background-color: var(--color-ink);
  color: var(--color-white);
  padding: 4rem 0 2rem 0;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  margin-bottom: 3rem;
}

@media (min-width: 640px) {
  .footer-grid {
    grid-template-columns: 2fr 1fr 1fr 1fr;
  }
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-brand-title {
  color: var(--color-white);
  font-size: 1.4rem;
  font-weight: 800;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.9rem;
  max-width: 320px;
}

.footer-col h4 {
  color: var(--color-white);
  font-size: 1rem;
  margin-bottom: 1.25rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.75);
  font-size: 0.9rem;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: center;
  text-align: center;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

/* Accessibility focus styles */
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid var(--color-vermilion);
  outline-offset: 3px;
}