/* ==========================================================================
   BitzNet Geographic Atlas Catalog - Design System & Stylesheet
   Palette: Pearl #FCFBF7, Ocean Ink #183D50, Muted Coral #C77F6A, Pale Mist #E8F0EF
   ========================================================================== */

:root {
  --color-pearl: #FCFBF7;
  --color-ink: #183D50;
  --color-ink-subtle: #425A69;
  --color-ink-muted: #647B89;
  --color-coral: #C77F6A;
  --color-coral-dark: #A85E4B;
  --color-coral-light: #F7EDE9;
  --color-mist: #E8F0EF;
  --color-mist-light: #F3F7F6;
  --color-mist-border: #D1E0DE;
  --color-card-bg: #FFFFFF;
  --color-border: rgba(24, 61, 80, 0.16);
  --color-border-subtle: rgba(24, 61, 80, 0.08);

  --font-serif: "Songti SC", "SimSun", "Noto Serif SC", "STSong", "Songti", "Source Han Serif SC", Georgia, serif;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  --h1-size-desktop: 54px;
  --h1-size-mobile: 35px;
  --body-size: 17px;
  --line-height-body: 1.75;
  --line-height-heading: 1.25;

  --max-width: 1240px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  --shadow-subtle: 0 4px 16px rgba(24, 61, 80, 0.05);
  --shadow-atlas: 0 10px 30px rgba(24, 61, 80, 0.08);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--color-pearl);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: var(--body-size);
  line-height: var(--line-height-body);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 1px 1px, rgba(24, 61, 80, 0.06) 1px, transparent 0);
  background-size: 32px 32px;
}

/* Accessibility: Skip link */
.skip-link {
  position: absolute;
  top: -60px;
  left: 20px;
  background: var(--color-ink);
  color: var(--color-pearl);
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  z-index: 9999;
  text-decoration: none;
  font-weight: 600;
  transition: top 0.2s ease;
}
.skip-link:focus {
  top: 16px;
}

/* Typography */
h1, h2, h3, h4, .serif-heading {
  font-family: var(--font-serif);
  color: var(--color-ink);
  line-height: var(--line-height-heading);
  letter-spacing: -0.01em;
}

h1 {
  font-size: var(--h1-size-mobile);
  font-weight: 700;
  margin-bottom: 1.25rem;
}

h2 {
  font-size: 2rem;
  margin-bottom: 1rem;
}

h3 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}

p {
  color: var(--color-ink-subtle);
  margin-bottom: 1.25rem;
}

a {
  color: var(--color-ink);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 0.2s ease, border-color 0.2s ease;
}

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

.mono-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-coral);
  display: inline-block;
  margin-bottom: 0.5rem;
}

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

/* Top Coordinate Bar */
.top-coord-bar {
  background: var(--color-mist);
  border-bottom: 1px solid var(--color-mist-border);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
  padding: 0.35rem 0;
}
.top-coord-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.coord-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}
.coord-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-coral);
}

/* Header & Navigation */
.site-header {
  background: rgba(252, 251, 247, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  font-family: var(--font-serif);
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--color-ink);
}

.brand-symbol {
  width: 34px;
  height: 34px;
  border: 1.5px solid var(--color-ink);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  background: var(--color-mist);
}
.brand-symbol::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border-top: 1.5px solid var(--color-coral);
  border-right: 1.5px solid var(--color-coral);
  transform: rotate(45deg);
}

.nav-desktop {
  display: none;
}

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

.nav-links a {
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-ink);
  position: relative;
  padding: 0.35rem 0;
}
.nav-links a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--color-coral);
  transition: width 0.25s ease;
}
.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.header-cta-group {
  display: none;
  align-items: center;
  gap: 1rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.6rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s ease;
  line-height: 1.2;
}

.btn-primary {
  background: var(--color-ink);
  color: var(--color-pearl);
  border: 1.5px solid var(--color-ink);
}
.btn-primary:hover {
  background: var(--color-coral);
  border-color: var(--color-coral);
  color: #FFFFFF;
}

.btn-secondary {
  background: transparent;
  color: var(--color-ink);
  border: 1.5px solid var(--color-ink);
}
.btn-secondary:hover {
  background: var(--color-mist);
  color: var(--color-ink);
}

.btn-coral {
  background: var(--color-coral);
  color: #FFFFFF;
  border: 1.5px solid var(--color-coral);
}
.btn-coral:hover {
  background: var(--color-coral-dark);
  border-color: var(--color-coral-dark);
  color: #FFFFFF;
}

.btn-sm {
  padding: 0.45rem 1rem;
  font-size: 0.85rem;
}

/* Mobile Toggle */
.mobile-toggle {
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  width: 32px;
  height: 32px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 1001;
}
.mobile-toggle span {
  width: 100%;
  height: 2px;
  background: var(--color-ink);
  transition: all 0.3s ease;
  transform-origin: 1px center;
}
.mobile-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: rotate(45deg);
}
.mobile-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.mobile-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: rotate(-45deg);
}

/* Mobile Menu Drawer */
.mobile-drawer {
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-pearl);
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  transform: translateY(-110%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s;
  z-index: 999;
  border-bottom: 2px solid var(--color-ink);
  overflow-y: auto;
}
.mobile-drawer.open {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}
.mobile-drawer .nav-links {
  flex-direction: column;
  align-items: flex-start;
  gap: 1.25rem;
  width: 100%;
}
.mobile-drawer .nav-links a {
  font-size: 1.15rem;
  font-family: var(--font-serif);
  width: 100%;
  padding: 0.5rem 0;
  border-bottom: 1px dashed var(--color-border);
}
.mobile-drawer-cta {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-top: 1rem;
}

/* Section styling with Atlas Page Aesthetic */
.section {
  padding: 4.5rem 0;
  position: relative;
}
.section-alt {
  background: var(--color-mist-light);
  border-top: 1px solid var(--color-mist-border);
  border-bottom: 1px solid var(--color-mist-border);
}

.section-header {
  margin-bottom: 3rem;
  position: relative;
}
.section-header.text-center {
  text-align: center;
}
.section-header .mono-tag {
  margin-bottom: 0.6rem;
}
.section-subtitle {
  font-size: 1.05rem;
  max-width: 680px;
  margin-top: 0.5rem;
  margin-bottom: 0;
}
.section-header.text-center .section-subtitle {
  margin-left: auto;
  margin-right: auto;
}

/* Atlas Page Fold Divider */
.atlas-divider {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin: 3.5rem 0;
  position: relative;
}
.atlas-divider::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 1px;
  background: var(--color-border);
  z-index: 1;
}
.atlas-divider-label {
  position: relative;
  z-index: 2;
  background: var(--color-pearl);
  padding: 0 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
  letter-spacing: 0.1em;
  margin: 0 auto;
}
.section-alt .atlas-divider-label {
  background: var(--color-mist-light);
}

/* ==========================================================================
   Hero Section: Left Copy + Right Network Atlas (SVG/CSS)
   ========================================================================== */
.hero-section {
  padding: 3rem 0 4.5rem;
  position: relative;
  overflow: hidden;
}

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

.hero-copy {
  display: flex;
  flex-direction: column;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--color-mist);
  border: 1px solid var(--color-mist-border);
  padding: 0.3rem 0.85rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-ink);
  width: fit-content;
  margin-bottom: 1.25rem;
}

.hero-title {
  color: var(--color-ink);
  line-height: 1.18;
  margin-bottom: 1.5rem;
}
.hero-title .brand-highlight {
  color: var(--color-coral);
  position: relative;
  display: inline-block;
}

.hero-intro {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--color-ink-subtle);
  margin-bottom: 2rem;
}

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

.hero-meta-points {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px dashed var(--color-border);
}
.hero-meta-item {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.88rem;
  color: var(--color-ink-muted);
  font-family: var(--font-mono);
}
.hero-meta-item svg {
  width: 14px;
  height: 14px;
  stroke: var(--color-coral);
}

/* Network Atlas Visual Box */
.atlas-visual-card {
  background: #FFFFFF;
  border: 1.5px solid var(--color-ink);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-atlas);
  overflow: hidden;
  position: relative;
}

.atlas-card-header {
  background: var(--color-mist);
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--color-mist-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-ink);
}

.atlas-card-body {
  position: relative;
  padding: 1.25rem;
  background-color: #FAFCFB;
}

.atlas-svg {
  width: 100%;
  height: auto;
  display: block;
  overflow: visible;
}

/* Route Path Drawing Animation - Executes once then stops */
@keyframes drawRouteLine {
  0% {
    stroke-dashoffset: 750;
  }
  100% {
    stroke-dashoffset: 0;
  }
}

.route-drawn {
  stroke-dasharray: 750;
  stroke-dashoffset: 750;
  animation: drawRouteLine 2.8s cubic-bezier(0.2, 0.8, 0.25, 1) forwards;
  animation-iteration-count: 1;
}

.atlas-card-footer {
  background: #FFFFFF;
  border-top: 1px solid var(--color-border-subtle);
  padding: 0.75rem 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
}
.atlas-legend {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}
.legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}
.legend-dot.coral { background: var(--color-coral); }
.legend-dot.ink { background: var(--color-ink); }

/* ==========================================================================
   Advantages: Three Atlas "Entries" (档案条目编号风格)
   ========================================================================== */
.advantages-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}

.atlas-entry-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem 1.75rem;
  position: relative;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}
.atlas-entry-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-subtle);
  border-color: var(--color-ink);
}

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

.entry-index {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--color-coral);
  letter-spacing: 0.05em;
}

.entry-coordinate {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-ink-muted);
}

.entry-title {
  font-size: 1.35rem;
  margin-bottom: 0.85rem;
}

.entry-desc {
  font-size: 0.98rem;
  line-height: 1.75;
  color: var(--color-ink-subtle);
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.entry-checklist {
  list-style: none;
  font-size: 0.88rem;
  color: var(--color-ink);
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  border-top: 1px solid var(--color-border-subtle);
  padding-top: 0.85rem;
}
.entry-checklist li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.entry-checklist li::before {
  content: "■";
  color: var(--color-coral);
  font-size: 0.65rem;
}

/* ==========================================================================
   Global Nodes: Region Directory
   ========================================================================== */
.region-directory {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.region-panel {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  position: relative;
}

.region-panel-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 1rem;
  border-bottom: 1.5px solid var(--color-mist-border);
  padding-bottom: 0.6rem;
}

.region-name {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-ink);
}

.region-code {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-coral);
  letter-spacing: 0.05em;
}

.region-node-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
  margin-top: 1rem;
}

.node-item {
  background: var(--color-mist-light);
  border: 1px solid var(--color-mist-border);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.node-title-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.node-indicator {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-coral);
}

.node-label {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--color-ink);
}

.node-tags {
  display: flex;
  gap: 0.4rem;
}

.node-tag {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 0.15rem 0.45rem;
  border-radius: 2px;
  background: rgba(24, 61, 80, 0.08);
  color: var(--color-ink-subtle);
}

.nodes-disclaimer {
  margin-top: 1.5rem;
  font-size: 0.85rem;
  color: var(--color-ink-muted);
  border-left: 2px solid var(--color-coral);
  padding-left: 0.85rem;
  font-style: normal;
}

/* ==========================================================================
   AI & Streaming Use Cases (Structured, Not Logo Wall)
   ========================================================================== */
.usecases-container {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.usecase-category {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem 1.75rem;
}

.category-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-coral);
  text-transform: uppercase;
  margin-bottom: 0.5rem;
  display: block;
}

.category-title {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

.category-summary {
  font-size: 0.95rem;
  color: var(--color-ink-subtle);
  margin-bottom: 1.5rem;
}

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

.scenario-card {
  border-left: 3px solid var(--color-mist-border);
  padding-left: 1.25rem;
  transition: border-color 0.2s ease;
}
.scenario-card:hover {
  border-left-color: var(--color-coral);
}

.scenario-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 0.35rem;
}

.scenario-name {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-ink);
}

.scenario-brand-tags {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
}

.scenario-body {
  font-size: 0.92rem;
  line-height: 1.65;
  color: var(--color-ink-subtle);
  margin-bottom: 0.4rem;
}

.scenario-req {
  font-size: 0.8rem;
  color: var(--color-coral-dark);
  font-family: var(--font-mono);
}

/* ==========================================================================
   Pricing Reference Table
   ========================================================================== */
.table-responsive-wrapper {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-card-bg);
  box-shadow: var(--shadow-subtle);
  margin-bottom: 1.5rem;
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  min-width: 680px;
}

.pricing-table th,
.pricing-table td {
  padding: 1.1rem 1.25rem;
  border-bottom: 1px solid var(--color-border-subtle);
  font-size: 0.92rem;
}

.pricing-table th {
  background: var(--color-mist);
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-ink);
  letter-spacing: 0.02em;
}

.pricing-table tbody tr:hover {
  background: var(--color-mist-light);
}

.pricing-tier-name {
  font-weight: 700;
  color: var(--color-ink);
  display: block;
}

.pricing-tier-code {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
}

.price-val {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--color-ink);
}

.editorial-note {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-coral);
  display: block;
  margin-top: 0.2rem;
}

.pricing-table-disclaimer {
  background: var(--color-mist);
  border: 1px solid var(--color-mist-border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  font-size: 0.85rem;
  color: var(--color-ink-subtle);
  line-height: 1.6;
}

/* ==========================================================================
   Nine SEO Article Cards (Catalog Record Style)
   3 columns desktop, 2 columns tablet, 1 column mobile
   ========================================================================== */
.articles-catalog-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}

.article-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  text-decoration: none;
  color: inherit;
}
.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-ink);
  box-shadow: var(--shadow-atlas);
}

.card-archive-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px dashed var(--color-border);
  padding-bottom: 0.65rem;
  margin-bottom: 0.85rem;
}

.card-cat-id {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-coral);
  font-weight: 600;
}

.card-date {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
}

.card-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--color-ink);
  margin-bottom: 0.75rem;
}
.article-card:hover .card-title {
  color: var(--color-coral);
}

.card-desc {
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--color-ink-subtle);
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.card-meta-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--color-border-subtle);
  padding-top: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-ink-muted);
}

.card-wordcount {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.card-action {
  color: var(--color-ink);
  font-weight: 600;
}
.article-card:hover .card-action {
  color: var(--color-coral);
}

/* ==========================================================================
   Testimonials (Clearly Labeled Sample Feedbacks)
   ========================================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.testimonial-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  position: relative;
}

.sample-label-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.2rem 0.5rem;
  background: var(--color-mist);
  color: var(--color-coral-dark);
  border: 1px solid var(--color-mist-border);
  border-radius: 2px;
  margin-bottom: 1rem;
}

.testimonial-quote {
  font-size: 0.96rem;
  line-height: 1.75;
  color: var(--color-ink-subtle);
  margin-bottom: 1.25rem;
  font-style: normal;
}

.testimonial-author-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px dashed var(--color-border);
  padding-top: 0.75rem;
}

.author-role {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--color-ink);
}

.author-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-ink-muted);
}

/* ==========================================================================
   FAQ Accordion
   ========================================================================== */
.faq-accordion {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--color-card-bg);
  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-ink);
}

.faq-summary {
  padding: 1.25rem 1.5rem;
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-ink);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  list-style: none;
}
.faq-summary::-webkit-details-marker {
  display: none;
}
.faq-icon {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.25s ease;
  color: var(--color-coral);
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 400;
}
.faq-item[open] .faq-icon {
  transform: rotate(45deg);
}

.faq-content {
  padding: 0 1.5rem 1.5rem 1.5rem;
  color: var(--color-ink-subtle);
  font-size: 0.96rem;
  line-height: 1.75;
  border-top: 1px dashed var(--color-border-subtle);
  padding-top: 1rem;
}
.faq-content p:last-child {
  margin-bottom: 0;
}

/* ==========================================================================
   Article Detail & Subpage Layouts
   ========================================================================== */
.article-header {
  padding: 3rem 0 2rem;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 2.5rem;
}

.breadcrumbs {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-ink-muted);
  margin-bottom: 1.25rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}
.breadcrumbs a {
  text-decoration: none;
  color: var(--color-ink);
}
.breadcrumbs a:hover {
  color: var(--color-coral);
}
.breadcrumbs .crumb-sep {
  color: var(--color-ink-muted);
}

.article-title {
  margin-bottom: 1rem;
  font-size: 2.35rem;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-ink-muted);
}

.article-container {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  margin-bottom: 4rem;
}

.article-body {
  font-size: 1.05rem;
  line-height: 1.85;
  color: var(--color-ink-subtle);
}

.article-body h2 {
  font-size: 1.75rem;
  margin-top: 2.5rem;
  margin-bottom: 1.2rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-border-subtle);
}

.article-body h3 {
  font-size: 1.3rem;
  margin-top: 1.8rem;
  margin-bottom: 0.75rem;
}

.article-body ul, .article-body ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}
.article-body li {
  margin-bottom: 0.5rem;
}

.article-body blockquote {
  background: var(--color-mist-light);
  border-left: 4px solid var(--color-coral);
  padding: 1rem 1.5rem;
  margin: 1.75rem 0;
  font-style: normal;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.article-body code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--color-mist);
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
  color: var(--color-ink);
}

.article-body pre {
  background: var(--color-ink);
  color: #F8FAFC;
  padding: 1.25rem;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin: 1.5rem 0;
}
.article-body pre code {
  background: transparent;
  color: inherit;
  padding: 0;
}

.article-cta-box {
  background: var(--color-mist);
  border: 1.5px solid var(--color-ink);
  border-radius: var(--radius-md);
  padding: 2rem;
  margin: 2.5rem 0;
  text-align: center;
}
.article-cta-box h3 {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
}

.related-articles {
  border-top: 1px solid var(--color-border);
  padding-top: 2.5rem;
  margin-top: 3rem;
}
.related-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 1.25rem;
}
.related-item {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 1.2rem;
  text-decoration: none;
  display: block;
}
.related-item:hover {
  border-color: var(--color-coral);
}
.related-item-title {
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--color-ink);
  font-size: 1.05rem;
  margin-bottom: 0.35rem;
}
.related-item-desc {
  font-size: 0.85rem;
  color: var(--color-ink-muted);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  background: var(--color-ink);
  color: var(--color-pearl);
  padding: 4rem 0 2rem;
  margin-top: auto;
  border-top: 3px solid var(--color-coral);
}

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

.footer-brand {
  max-width: 380px;
}
.footer-logo {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-pearl);
  text-decoration: none;
  display: inline-block;
  margin-bottom: 1rem;
}
.footer-brand p {
  color: #A3BDC9;
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer-nav-col h4 {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-coral);
  margin-bottom: 1.2rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.footer-links a {
  color: #CCDCE3;
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s ease;
}
.footer-links a:hover {
  color: #FFFFFF;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  font-size: 0.82rem;
  color: #8BA8B6;
  font-family: var(--font-mono);
}

/* ==========================================================================
   Responsive Breakpoints: 768px (Tablet), 1024px (Laptop), 1440px (Desktop)
   ========================================================================== */
@media (min-width: 768px) {
  .top-coord-inner {
    font-size: 0.75rem;
  }

  .nav-desktop {
    display: block;
  }
  .header-cta-group {
    display: flex;
  }
  .mobile-toggle {
    display: none;
  }
  .mobile-drawer {
    display: none;
  }

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

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

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

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

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

  .footer-top {
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
  }

  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

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

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

  .hero-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 3.5rem;
  }

  .region-directory {
    grid-template-columns: repeat(4, 1fr);
  }

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

  .testimonials-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (min-width: 1440px) {
  :root {
    --max-width: 1320px;
  }
}

/* Accessibility: Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001s !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001s !important;
    scroll-behavior: auto !important;
  }
  .route-drawn {
    animation: none;
    stroke-dashoffset: 0;
  }
}