/* ==========================================================================
   TECHNICAL MANUAL DESIGN SYSTEM - YINGZI 
   Colors:
     Cool White: #FAFBFB
     Blue-Black: #26323C
     Muted Amber: #C59B57
     Pale Blue-Gray: #E7EDF0
   Typography:
     Heading & Body: Humanist system sans-serif
     Instructional Labels: Monospace
   ========================================================================== */

:root {
  --bg-primary: #FAFBFB;
  --bg-surface: #FFFFFF;
  --bg-subtle: #F3F6F8;
  --bg-card: #FAFBFB;
  --border-subtle: #E7EDF0;
  --border-strong: #26323C;
  --text-main: #26323C;
  --text-muted: #536270;
  --text-light: #7E8D9B;
  --accent-amber: #C59B57;
  --accent-amber-light: #FBF6EE;
  --accent-amber-border: #D8B984;
  --font-humanist: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --shadow-manual: 0 1px 3px rgba(38, 50, 60, 0.06), 0 4px 12px rgba(38, 50, 60, 0.04);
  --shadow-manual-elevated: 0 4px 16px rgba(38, 50, 60, 0.08);
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --container-max: 1200px;
}

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

html {
  font-size: 18px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-humanist);
  font-size: 1rem;
  line-height: 1.68;
  color: var(--text-main);
  background-color: var(--bg-primary);
  background-image: radial-gradient(var(--border-subtle) 1px, transparent 1px);
  background-size: 24px 24px;
  background-position: -1px -1px;
}

/* 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;
  }
}

/* Focus styles for accessibility */
a:focus-visible, button:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 2px solid var(--accent-amber);
  outline-offset: 3px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-humanist);
  color: var(--text-main);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 33px;
  margin-bottom: 1rem;
}

@media (min-width: 1024px) {
  h1 {
    font-size: 47px;
  }
}

h2 {
  font-size: 1.85rem;
  margin-bottom: 0.75rem;
}

h3 {
  font-size: 1.35rem;
  margin-bottom: 0.5rem;
}

p {
  margin-bottom: 1.15rem;
}

a {
  color: var(--text-main);
  text-decoration: underline;
  text-decoration-color: var(--accent-amber);
  text-underline-offset: 4px;
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}

a:hover {
  color: var(--accent-amber);
}

/* Monospace Instructional Labels */
.manual-label, .tech-tag, .spec-code, .doc-id, .chapter-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.chapter-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  border: 1px solid var(--accent-amber-border);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  margin-bottom: 0.85rem;
  font-weight: 600;
}

.doc-id {
  color: var(--text-light);
  border-left: 2px solid var(--accent-amber);
  padding-left: 0.5rem;
}

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

.section {
  padding: 4.5rem 0;
  border-bottom: 1px solid var(--border-subtle);
  position: relative;
}

.section-header {
  margin-bottom: 2.5rem;
}

.section-header p {
  color: var(--text-muted);
  max-width: 780px;
  font-size: 1.05rem;
}

/* Manual Callout Line & Margin Note */
.manual-callout {
  border-left: 3px solid var(--accent-amber);
  background-color: var(--accent-amber-light);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.manual-callout-title {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent-amber);
  text-transform: uppercase;
  margin-bottom: 0.35rem;
  display: block;
}

.manual-callout p:last-child {
  margin-bottom: 0;
  font-size: 0.95rem;
  color: var(--text-main);
}

.margin-note {
  font-size: 0.88rem;
  color: var(--text-muted);
  background: var(--bg-subtle);
  border: 1px dashed var(--border-subtle);
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  margin: 1rem 0;
}

/* Navigation Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(250, 251, 251, 0.94);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  font-weight: 700;
  color: var(--text-main);
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: var(--text-main);
  border: 1px solid var(--accent-amber);
  border-radius: var(--radius-sm);
  display: grid;
  place-items: center;
  color: var(--accent-amber);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: bold;
}

.brand-text {
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}

.brand-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  border: 1px solid var(--accent-amber-border);
  padding: 0.1rem 0.35rem;
  border-radius: 2px;
  margin-left: 0.35rem;
}

.main-nav {
  display: none;
}

.nav-links {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 1.75rem;
}

.nav-links a {
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-main);
  padding: 0.4rem 0.2rem;
  position: relative;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--accent-amber);
}

.nav-actions {
  display: none;
  align-items: center;
  gap: 1rem;
}

/* CTA Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.4rem;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
  cursor: pointer;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--accent-amber);
  color: #FFFFFF;
  border: 1px solid var(--accent-amber);
  text-decoration: none;
}

.btn-primary:hover {
  background-color: #B28845;
  border-color: #B28845;
  color: #FFFFFF;
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: var(--bg-surface);
  color: var(--text-main);
  border: 1px solid var(--border-subtle);
  text-decoration: none;
}

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

.btn-mono-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  opacity: 0.85;
}

/* Mobile Menu Toggle */
.mobile-toggle {
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  width: 32px;
  height: 32px;
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 6px;
  cursor: pointer;
}

.mobile-toggle span {
  width: 100%;
  height: 2px;
  background-color: var(--text-main);
  transition: all 0.2s ease;
}

.mobile-drawer {
  display: none;
  position: fixed;
  top: 70px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-primary);
  border-top: 1px solid var(--border-subtle);
  padding: 1.5rem;
  overflow-y: auto;
  z-index: 99;
}

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

.mobile-nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.mobile-nav-links a {
  font-size: 1.15rem;
  font-weight: 600;
  text-decoration: none;
  display: block;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

@media (min-width: 1024px) {
  .main-nav {
    display: block;
  }
  .nav-actions {
    display: flex;
  }
  .mobile-toggle {
    display: none;
  }
  .mobile-drawer {
    display: none !important;
  }
}

/* ==========================================================================
   HERO SECTION: Left Text + Right Network Dashboard (Manual Diagram)
   ========================================================================== */
.hero-section {
  padding: 3.5rem 0 4.5rem;
  border-bottom: 1px solid var(--border-subtle);
  background: linear-gradient(180deg, rgba(231, 237, 240, 0.3) 0%, rgba(250, 251, 251, 0) 100%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: center;
}

@media (min-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 3.5rem;
  }
}

.hero-content .lead {
  font-size: 1.15rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2rem;
}

.hero-specs-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 0.75rem;
  padding-top: 1.5rem;
  border-top: 1px dashed var(--border-subtle);
}

.hero-spec-item {
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.hero-spec-item .label {
  color: var(--text-light);
  display: block;
  margin-bottom: 0.2rem;
}

.hero-spec-item .val {
  font-weight: 700;
  color: var(--text-main);
}

/* Network Dashboard Manual Diagram */
.network-dashboard-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-manual-elevated);
  overflow: hidden;
}

.dashboard-header {
  background: var(--text-main);
  color: var(--bg-primary);
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 2px solid var(--accent-amber);
}

.dashboard-title {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.status-indicator {
  display: inline-block;
  width: 8px;
  height: 8px;
  background-color: var(--accent-amber);
  border-radius: 50%;
}

.dashboard-meta {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-amber);
}

.dashboard-body {
  padding: 1.25rem;
}

.diagram-blueprint {
  border: 1px solid var(--border-subtle);
  background: var(--bg-subtle);
  border-radius: var(--radius-sm);
  padding: 1rem;
  margin-bottom: 1.25rem;
}

.diagram-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 0;
  border-bottom: 1px dashed var(--border-subtle);
  font-size: 0.85rem;
}

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

.diagram-node-name {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--text-main);
}

.diagram-route-info {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  padding: 0.15rem 0.5rem;
  border-radius: 2px;
  border: 1px solid var(--accent-amber-border);
}

.dashboard-disclaimer {
  font-size: 0.75rem;
  color: var(--text-light);
  line-height: 1.5;
  background: var(--bg-primary);
  border-left: 2px solid var(--accent-amber);
  padding: 0.5rem 0.75rem;
}

/* ==========================================================================
   CHAPTER 01: ADVANTAGES (ILLUSTRATED EXPLANATIONS)
   ========================================================================== */
.benefits-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}

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

.benefit-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-top: 3px solid var(--accent-amber);
  padding: 1.75rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-manual);
  display: flex;
  flex-direction: column;
}

.benefit-card:hover {
  border-color: var(--accent-amber);
}

.schematic-box {
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 1rem;
  margin-bottom: 1.25rem;
  min-height: 110px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
}

.schematic-flow {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-main);
  width: 100%;
  justify-content: center;
}

.flow-step {
  border: 1px solid var(--border-strong);
  padding: 0.25rem 0.5rem;
  background: #FFF;
  border-radius: 2px;
}

.flow-arrow {
  color: var(--accent-amber);
  font-weight: bold;
}

.benefit-title {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.benefit-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ==========================================================================
   CHAPTER 02: REGIONAL REFERENCE PANEL (NODES)
   ========================================================================== */
.nodes-reference-panel {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .nodes-reference-panel {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

.region-node-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  position: relative;
}

.region-node-card:hover {
  border-color: var(--text-main);
}

.region-code-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  border: 1px solid var(--accent-amber-border);
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: 0.75rem;
}

.region-specs-table {
  width: 100%;
  margin-top: 1rem;
  font-size: 0.85rem;
  border-collapse: collapse;
}

.region-specs-table td {
  padding: 0.4rem 0;
  border-bottom: 1px dashed var(--border-subtle);
}

.region-specs-table td:first-child {
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  width: 40%;
}

.region-specs-table td:last-child {
  font-weight: 600;
  color: var(--text-main);
  text-align: right;
}

/* ==========================================================================
   CHAPTER 03: AI & STREAMING SCENARIO WALKTHROUGHS
   ========================================================================== */
.scenario-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 1024px) {
  .scenario-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.scenario-panel {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 2rem;
  box-shadow: var(--shadow-manual);
}

.scenario-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 0.75rem;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.tag-pill {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 0.25rem 0.6rem;
  border-radius: 3px;
}

.walkthrough-step-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.walkthrough-step {
  border-left: 2px solid var(--border-subtle);
  padding-left: 1rem;
  position: relative;
}

.walkthrough-step:hover {
  border-left-color: var(--accent-amber);
}

.step-number {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-amber);
  font-weight: bold;
  display: block;
  margin-bottom: 0.25rem;
}

.step-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* ==========================================================================
   CHAPTER 04: PRICING (CONCISE SPECIFICATION COMPARISON)
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

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

.pricing-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 2rem 1.5rem;
  position: relative;
  display: flex;
  flex-direction: column;
}

.pricing-card.featured {
  border: 2px solid var(--accent-amber);
  box-shadow: var(--shadow-manual-elevated);
}

.pricing-card-badge {
  position: absolute;
  top: -12px;
  right: 1.5rem;
  background: var(--accent-amber);
  color: #FFF;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
}

.package-name {
  font-size: 1.35rem;
  margin-bottom: 0.25rem;
}

.package-price-wrap {
  margin: 1.25rem 0;
  padding-bottom: 1.25rem;
  border-bottom: 1px dashed var(--border-subtle);
}

.package-price {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--text-main);
  font-family: var(--font-humanist);
}

.package-cycle {
  font-size: 0.85rem;
  color: var(--text-light);
}

.spec-editorial-notice {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  border: 1px solid var(--accent-amber-border);
  padding: 0.2rem 0.5rem;
  border-radius: 2px;
  display: inline-block;
  margin-bottom: 0.75rem;
}

.pricing-specs-list {
  list-style: none;
  margin-bottom: 2rem;
  flex-grow: 1;
}

.pricing-specs-list li {
  font-size: 0.9rem;
  padding: 0.45rem 0;
  border-bottom: 1px solid var(--bg-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.pricing-specs-list .spec-label {
  color: var(--text-muted);
}

.pricing-specs-list .spec-val {
  font-weight: 600;
  color: var(--text-main);
}

/* ==========================================================================
   CHAPTER 05: GUIDE LIBRARY (NINE SEO ARTICLES)
   Layout: 3 cols desktop, 2 cols tablet, 1 col mobile
   ========================================================================== */
.library-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .library-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

.article-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transition: border-color 0.15s ease, transform 0.15s ease;
  text-decoration: none;
  color: inherit;
}

.article-card:hover {
  border-color: var(--accent-amber);
  transform: translateY(-2px);
  color: inherit;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
}

.article-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-amber);
  background: var(--accent-amber-light);
  border: 1px solid var(--accent-amber-border);
  padding: 0.15rem 0.45rem;
  border-radius: 2px;
}

.article-reading-time {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-light);
}

.article-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
  line-height: 1.4;
  color: var(--text-main);
}

.article-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.article-read-link {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent-amber);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

/* ==========================================================================
   CHAPTER 06: TESTIMONIALS (VISIBLY SAMPLE TEST LOGS)
   ========================================================================== */
.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: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  position: relative;
}

.testimonial-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-light);
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  padding: 0.15rem 0.5rem;
  border-radius: 2px;
  display: inline-block;
  margin-bottom: 1rem;
}

.testimonial-quote {
  font-size: 0.95rem;
  color: var(--text-main);
  line-height: 1.65;
  margin-bottom: 1.25rem;
  font-style: normal;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  border-top: 1px dashed var(--border-subtle);
  padding-top: 0.75rem;
}

.author-meta {
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.author-name {
  font-weight: 700;
  color: var(--text-main);
  display: block;
}

.author-role {
  color: var(--text-light);
}

/* ==========================================================================
   CHAPTER 07: FAQ ACCORDION
   ========================================================================== */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.faq-trigger {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 1.25rem 1.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  font-family: var(--font-humanist);
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  transition: color 0.15s ease;
}

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

.faq-icon {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  color: var(--accent-amber);
  transition: transform 0.2s ease;
}

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

.faq-body {
  display: none;
  padding: 0 1.5rem 1.25rem;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.65;
  border-top: 1px dashed var(--border-subtle);
  padding-top: 1rem;
}

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

/* ==========================================================================
   ARTICLE PAGE SPECIFIC STYLES
   ========================================================================== */
.article-header {
  padding: 3rem 0 2rem;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-surface);
}

.breadcrumb-nav {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  margin-bottom: 1.5rem;
  color: var(--text-light);
}

.breadcrumb-nav a {
  color: var(--text-muted);
  text-decoration: none;
}

.breadcrumb-nav a:hover {
  color: var(--accent-amber);
}

.breadcrumb-separator {
  margin: 0 0.5rem;
  color: var(--border-subtle);
}

.article-lead {
  font-size: 1.15rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 1.5rem;
}

.article-content {
  padding: 3rem 0;
  max-width: 860px;
  margin: 0 auto;
}

.article-content h2 {
  font-size: 1.65rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 0.5rem;
}

.article-content h3 {
  font-size: 1.25rem;
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
}

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

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

.tech-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  display: table;
}

@media (max-width: 767px) {
  .tech-table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    white-space: nowrap;
  }
}

.tech-table th, .tech-table td {
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-subtle);
  text-align: left;
}

.tech-table th {
  background: var(--bg-subtle);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-main);
}

.code-block {
  background: var(--text-main);
  color: #FAFBFB;
  padding: 1.25rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  overflow-x: auto;
  margin: 1.5rem 0;
  line-height: 1.5;
  border-left: 3px solid var(--accent-amber);
}

.related-articles {
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 2px dashed var(--border-subtle);
}

.related-links-list {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 1.25rem;
}

@media (min-width: 768px) {
  .related-links-list {
    grid-template-columns: 1fr 1fr;
  }
}

.related-link-card {
  display: block;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  text-decoration: none;
}

.related-link-card:hover {
  border-color: var(--accent-amber);
}

.related-link-card strong {
  display: block;
  font-size: 0.95rem;
  color: var(--text-main);
  margin-bottom: 0.25rem;
}

.related-link-card span {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  background: #1F2933;
  color: #E7EDF0;
  padding: 4rem 0 2rem;
  border-top: 3px solid var(--accent-amber);
}

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

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
  }
}

.footer-col h4 {
  color: #FAFBFB;
  font-size: 1rem;
  margin-bottom: 1.25rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-left: 2px solid var(--accent-amber);
  padding-left: 0.5rem;
}

.footer-col p {
  color: #A0B2C0;
  font-size: 0.85rem;
  line-height: 1.6;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.footer-links a {
  color: #B4C6D4;
  text-decoration: none;
  font-size: 0.88rem;
  transition: color 0.15s ease;
}

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

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid rgba(231, 237, 240, 0.15);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.8rem;
  color: #8295A5;
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
  }
}

.footer-bottom a {
  color: #8295A5;
  text-decoration: none;
}

.footer-bottom a:hover {
  color: var(--accent-amber);
}