/* ==========================================================================
   泰山机场 (TaishanNet) - 官方网站设计系统
   Design Direction: Editorial Technology
   Color System: Warm Ivory (#FAF8F5), Dark Plum (#281426), Copper Accents (#C86D51)
   Typography: Large Serif Headings + Compact Sans-Serif Interface
   ========================================================================== */

:root {
  /* Editorial Palette */
  --color-ivory-bg: #FAF7F2;
  --color-ivory-surface: #FFFFFF;
  --color-ivory-subtle: #F3EFE8;
  --color-ivory-muted: #E8E2D7;

  --color-plum-deep: #251224;
  --color-plum-primary: #381B34;
  --color-plum-secondary: #583954;
  --color-plum-muted: #7E657A;

  --color-copper: #C86D51;
  --color-copper-light: #E08B71;
  --color-copper-dark: #9E492F;
  --color-copper-soft: rgba(200, 109, 81, 0.12);
  --color-copper-glow: rgba(200, 109, 81, 0.28);

  --color-border: rgba(56, 27, 52, 0.12);
  --color-border-subtle: rgba(56, 27, 52, 0.06);
  --color-border-copper: rgba(200, 109, 81, 0.35);

  --color-text-main: #251224;
  --color-text-body: #4A3546;
  --color-text-muted: #756172;
  --color-text-light: #9B8998;

  --color-success: #2E7D52;
  --color-warning: #C7771E;

  /* Typography */
  --font-serif: "Songti SC", "SimSun", "Noto Serif CJK SC", "Source Han Serif SC", "STSong", "Playfair Display", Georgia, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Consolas", "Courier New", monospace;

  /* Spacing */
  --container-max: 1220px;
  --container-narrow: 860px;
  --section-padding: 5.5rem 1.5rem;
  --section-padding-sm: 3.5rem 1.25rem;

  /* Shadows & Depth */
  --shadow-subtle: 0 4px 20px rgba(37, 18, 36, 0.04);
  --shadow-card: 0 10px 30px rgba(37, 18, 36, 0.06);
  --shadow-hover: 0 16px 36px rgba(37, 18, 36, 0.10);
  --shadow-copper: 0 12px 28px rgba(200, 109, 81, 0.18);

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 10px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 0.18s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-normal: 0.28s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Base Reset & Box Sizing */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--color-ivory-bg);
  color: var(--color-text-main);
  text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.68;
  color: var(--color-text-body);
  background-color: var(--color-ivory-bg);
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Headings with Editorial Serif Character */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--color-plum-deep);
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(2.1rem, 4.2vw, 3.4rem);
  line-height: 1.2;
}

h2 {
  font-size: clamp(1.75rem, 3.2vw, 2.5rem);
  line-height: 1.25;
}

h3 {
  font-size: clamp(1.25rem, 2vw, 1.55rem);
  line-height: 1.35;
}

h4 {
  font-size: 1.15rem;
}

p {
  margin-bottom: 1.1rem;
  font-size: 1rem;
  line-height: 1.72;
  color: var(--color-text-body);
}

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

a {
  color: var(--color-copper-dark);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Utility Containers */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

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

.section {
  padding: var(--section-padding);
  position: relative;
}

.section-alt {
  background-color: var(--color-ivory-subtle);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

/* Section Header Typography */
.section-header {
  margin-bottom: 3.2rem;
  max-width: 780px;
}

.section-header.center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  border: 1px solid var(--color-border-copper);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  margin-bottom: 1rem;
}

.section-header h2 {
  margin-bottom: 0.9rem;
}

.section-header p {
  font-size: 1.08rem;
  color: var(--color-text-muted);
}

/* Buttons & Editorial Action Components */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-sans);
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  padding: 0.78rem 1.6rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--color-plum-primary);
  color: #FFFFFF;
  border-color: var(--color-plum-primary);
  box-shadow: 0 4px 14px rgba(37, 18, 36, 0.18);
}

.btn-primary:hover {
  background-color: var(--color-plum-deep);
  color: #FFFFFF;
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(37, 18, 36, 0.25);
}

.btn-copper {
  background: linear-gradient(135deg, var(--color-copper) 0%, #D47B5E 100%);
  color: #FFFFFF;
  border-color: var(--color-copper);
  box-shadow: var(--shadow-copper);
}

.btn-copper:hover {
  background: linear-gradient(135deg, var(--color-copper-dark) 0%, var(--color-copper) 100%);
  color: #FFFFFF;
  transform: translateY(-2px);
  box-shadow: 0 14px 30px rgba(200, 109, 81, 0.32);
}

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

.btn-secondary:hover {
  background-color: var(--color-ivory-subtle);
  border-color: var(--color-plum-secondary);
  color: var(--color-plum-deep);
  transform: translateY(-1px);
}

.btn-sm {
  padding: 0.45rem 1rem;
  font-size: 0.82rem;
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(250, 247, 242, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition-normal);
}

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

.brand-wrap {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none;
}

.brand-icon {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--color-plum-primary) 0%, var(--color-plum-deep) 100%);
  border: 1px solid var(--color-border-copper);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.15rem;
  box-shadow: 0 2px 8px rgba(37, 18, 36, 0.14);
}

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

.brand-name {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-plum-deep);
  line-height: 1.15;
  letter-spacing: -0.01em;
}

.brand-tagline {
  font-size: 0.72rem;
  color: var(--color-copper-dark);
  letter-spacing: 0.08em;
  font-family: var(--font-mono);
  text-transform: uppercase;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 1.6rem;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-body);
  transition: color var(--transition-fast);
  position: relative;
  padding: 0.25rem 0;
}

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

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0%;
  height: 2px;
  background-color: var(--color-copper);
  transition: width var(--transition-fast);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-link-badge {
  display: inline-block;
  font-size: 0.68rem;
  padding: 0.12rem 0.45rem;
  background-color: var(--color-copper-soft);
  color: var(--color-copper-dark);
  border-radius: var(--radius-full);
  margin-left: 0.25rem;
  vertical-align: middle;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.hamburger-btn {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.5rem;
  cursor: pointer;
  color: var(--color-plum-deep);
}

.hamburger-btn svg {
  display: block;
  width: 22px;
  height: 22px;
}

/* Mobile Nav Drawer */
.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(250, 247, 242, 0.98);
  backdrop-filter: blur(14px);
  z-index: 99;
  padding: 1.8rem 1.5rem;
  overflow-y: auto;
  border-top: 1px solid var(--color-border);
  flex-direction: column;
  justify-content: space-between;
}

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

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

.mobile-nav-links a {
  font-family: var(--font-serif);
  font-size: 1.28rem;
  font-weight: 600;
  color: var(--color-plum-deep);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.mobile-nav-footer {
  border-top: 1px solid var(--color-border);
  padding-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

/* ==========================================================================
   Hero Section: Asymmetrical Editorial + 3D Perspective Orbital Telemetry
   ========================================================================== */
.hero-section {
  padding: 4.8rem 1.5rem 5.5rem;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.95fr;
  gap: 3.5rem;
  align-items: center;
}

.hero-copy {
  max-width: 620px;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  border: 1px solid var(--color-border-copper);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  margin-bottom: 1.3rem;
}

.hero-title {
  font-size: clamp(2.2rem, 4.4vw, 3.6rem);
  line-height: 1.16;
  color: var(--color-plum-deep);
  margin-bottom: 1.3rem;
}

.hero-title .copper-accent {
  color: var(--color-copper);
  font-style: italic;
  font-weight: 400;
  display: inline-block;
}

.hero-desc {
  font-size: 1.12rem;
  line-height: 1.78;
  color: var(--color-text-body);
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2.2rem;
}

.hero-meta-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.8rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--color-border);
}

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

.meta-val {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-plum-deep);
  line-height: 1.2;
}

.meta-label {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

/* 3D Perspective Orbital Telemetry Board */
.hero-stage {
  perspective: 1100px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.telemetry-board {
  position: relative;
  width: 100%;
  max-width: 490px;
  background: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-hover);
  transform: rotateY(-6deg) rotateX(4deg);
  transition: transform var(--transition-normal);
}

.telemetry-board:hover {
  transform: rotateY(-2deg) rotateX(1deg);
}

.telemetry-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.6rem;
  padding-bottom: 0.9rem;
  border-bottom: 1px dashed var(--color-border);
}

.telemetry-title {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--color-plum-primary);
  letter-spacing: 0.08em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.live-pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--color-success);
  box-shadow: 0 0 0 3px rgba(46, 125, 82, 0.2);
}

.telemetry-status {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-copper-dark);
}

/* Rotating Orbital Visualization inside Hero Board */
.orbital-viewport {
  position: relative;
  width: 280px;
  height: 280px;
  margin: 0.5rem auto 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.orbital-ring {
  position: absolute;
  border-radius: 50%;
  border: 1px dashed rgba(56, 27, 52, 0.16);
  pointer-events: none;
}

.ring-outer {
  width: 270px;
  height: 270px;
  animation: orbitRotate 46s linear infinite;
}

.ring-mid {
  width: 190px;
  height: 190px;
  border-color: rgba(200, 109, 81, 0.35);
  animation: orbitRotateRev 32s linear infinite;
}

.ring-inner {
  width: 110px;
  height: 110px;
  animation: orbitRotate 20s linear infinite;
}

.orbital-node {
  position: absolute;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--color-copper);
  box-shadow: 0 0 10px var(--color-copper);
  top: -5px;
  left: 50%;
  transform: translateX(-50%);
}

.orbital-node.secondary {
  width: 8px;
  height: 8px;
  background-color: var(--color-plum-primary);
  box-shadow: 0 0 8px rgba(56, 27, 52, 0.4);
  top: auto;
  bottom: -4px;
}

.orbital-core {
  position: relative;
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--color-plum-primary) 0%, var(--color-plum-deep) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  box-shadow: 0 4px 16px rgba(37, 18, 36, 0.3);
  text-align: center;
  line-height: 1.15;
}

@keyframes orbitRotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes orbitRotateRev {
  from { transform: rotate(360deg); }
  to { transform: rotate(0deg); }
}

/* Telemetry Route Metrics */
.telemetry-metrics {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.metric-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  padding: 0.45rem 0.75rem;
  background-color: var(--color-ivory-subtle);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--color-copper);
}

.metric-city {
  font-weight: 600;
  color: var(--color-plum-deep);
}

.metric-line {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.metric-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--color-copper-dark);
}

/* ==========================================================================
   Core Advantages (Asymmetrical Editorial Bento: 1 Featured Large + 2 Stacked)
   ========================================================================== */
.advantages-bento {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  gap: 1.8rem;
  align-items: stretch;
}

.adv-featured-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 3rem 2.6rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.adv-featured-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-copper) 0%, var(--color-plum-primary) 100%);
}

.adv-icon-badge {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background-color: var(--color-copper-soft);
  color: var(--color-copper-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.6rem;
}

.adv-icon-badge svg {
  width: 24px;
  height: 24px;
}

.adv-featured-card h3 {
  font-size: 1.7rem;
  margin-bottom: 1.1rem;
}

.adv-featured-card p {
  font-size: 1.05rem;
  color: var(--color-text-body);
  line-height: 1.78;
  margin-bottom: 1.8rem;
}

.adv-features-list {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.9rem;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.adv-features-list li {
  font-size: 0.88rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-plum-deep);
  font-weight: 500;
}

.adv-features-list li::before {
  content: "✦";
  color: var(--color-copper);
}

.adv-stack {
  display: flex;
  flex-direction: column;
  gap: 1.8rem;
}

.adv-sub-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.2rem 2rem;
  box-shadow: var(--shadow-subtle);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.adv-sub-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-card);
  border-color: var(--color-border-copper);
}

.adv-sub-card h3 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}

.adv-sub-card p {
  font-size: 0.95rem;
  color: var(--color-text-body);
}

/* ==========================================================================
   Global Nodes Network (Geographic Editorial Matrix)
   ========================================================================== */
.nodes-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.node-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.8rem 1.5rem;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.node-card:hover {
  transform: translateY(-3px);
  border-color: var(--color-border-copper);
  box-shadow: var(--shadow-card);
}

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

.node-flag-wrap {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.node-flag {
  font-size: 1.4rem;
  line-height: 1;
}

.node-name {
  font-family: var(--font-serif);
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--color-plum-deep);
}

.node-code {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
}

.node-desc {
  font-size: 0.88rem;
  line-height: 1.62;
  color: var(--color-text-body);
  margin-bottom: 1.3rem;
}

.node-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: auto;
}

.node-tag {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  background-color: var(--color-ivory-subtle);
  border: 1px solid var(--color-border-subtle);
  color: var(--color-plum-secondary);
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-sm);
}

/* ==========================================================================
   AI & Streaming Scenarios (Open Editorial Layout with Diagram Pointers)
   ========================================================================== */
.scenarios-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
}

.scenario-panel {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.8rem 2.4rem;
  box-shadow: var(--shadow-card);
}

.scenario-panel h3 {
  font-size: 1.65rem;
  margin-bottom: 1rem;
}

.scenario-panel p {
  font-size: 1rem;
  color: var(--color-text-body);
  margin-bottom: 1.8rem;
}

.tool-capsules {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 2rem;
}

.tool-capsule {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.82rem;
  font-weight: 600;
  background-color: var(--color-ivory-subtle);
  color: var(--color-plum-primary);
  border: 1px solid var(--color-border);
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-full);
}

.capsule-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-copper);
}

.scenario-diagram {
  background-color: var(--color-ivory-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.4rem;
}

.diagram-step {
  display: flex;
  align-items: flex-start;
  gap: 0.8rem;
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
}

.diagram-step:last-child {
  margin-bottom: 0;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-text {
  color: var(--color-text-body);
  line-height: 1.55;
}

/* ==========================================================================
   Pricing Section (4 Clear Options with EXACTLY 1 Visually Recommended)
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.6rem;
  align-items: stretch;
}

.pricing-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.4rem 1.8rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-subtle);
  position: relative;
  transition: all var(--transition-normal);
}

.pricing-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

/* Visually Recommended Option */
.pricing-card.recommended {
  border: 2px solid var(--color-copper);
  box-shadow: var(--shadow-copper);
  background: linear-gradient(180deg, #FFFFFF 0%, #FDF9F5 100%);
  transform: scale(1.02);
  z-index: 2;
}

.pricing-card.recommended:hover {
  transform: scale(1.03) translateY(-4px);
}

.recommended-ribbon {
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--color-copper) 0%, #D47B5E 100%);
  color: #FFFFFF;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.28rem 1rem;
  border-radius: var(--radius-full);
  box-shadow: 0 4px 10px rgba(200, 109, 81, 0.35);
  white-space: nowrap;
}

.pricing-tier-name {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--color-plum-deep);
  margin-bottom: 0.35rem;
}

.pricing-subtitle {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-bottom: 1.6rem;
  min-height: 2.2em;
}

.pricing-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 0.35rem;
  margin-bottom: 0.4rem;
}

.price-currency {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  color: var(--color-plum-deep);
  font-weight: 700;
}

.price-amount {
  font-family: var(--font-mono);
  font-size: 2.45rem;
  font-weight: 700;
  color: var(--color-plum-deep);
  line-height: 1;
}

.price-period {
  font-size: 0.88rem;
  color: var(--color-text-muted);
}

.pricing-cycle-hint {
  font-size: 0.76rem;
  color: var(--color-copper-dark);
  font-family: var(--font-mono);
  margin-bottom: 1.8rem;
}

.pricing-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 2rem;
  padding-top: 1.4rem;
  border-top: 1px dashed var(--color-border);
}

.pricing-features li {
  font-size: 0.88rem;
  color: var(--color-text-body);
  display: flex;
  align-items: flex-start;
  gap: 0.55rem;
  line-height: 1.5;
}

.pricing-features li svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  margin-top: 2px;
  color: var(--color-copper);
}

.pricing-disclaimer {
  font-size: 0.72rem;
  color: var(--color-text-muted);
  text-align: center;
  margin-top: 0.75rem;
}

/* ==========================================================================
   9 SEO Articles Grid (3x3 Desktop, 2-Col Tablet, 1-Col Mobile)
   ========================================================================== */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.article-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.2rem 1.9rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-subtle);
  transition: all var(--transition-normal);
  position: relative;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-border-copper);
  box-shadow: var(--shadow-card);
}

.article-meta-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.85rem;
}

.article-category {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  padding: 0.22rem 0.6rem;
  border-radius: var(--radius-sm);
}

.article-read-time {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
}

.article-card-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.38;
  color: var(--color-plum-deep);
  margin-bottom: 0.85rem;
}

.article-card-title a {
  color: inherit;
  text-decoration: none;
}

.article-card-title a:hover {
  color: var(--color-copper-dark);
}

.article-excerpt {
  font-size: 0.9rem;
  line-height: 1.68;
  color: var(--color-text-body);
  margin-bottom: 1.6rem;
  flex-grow: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1.2rem;
  border-top: 1px solid var(--color-border-subtle);
  font-size: 0.82rem;
}

.article-date {
  color: var(--color-text-muted);
  font-family: var(--font-mono);
}

.article-read-link {
  font-weight: 600;
  color: var(--color-copper-dark);
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  transition: gap var(--transition-fast);
}

.article-card:hover .article-read-link {
  gap: 0.55rem;
}

/* ==========================================================================
   Testimonials (Editorial Pull Quotes)
   ========================================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.8rem;
}

.testimonial-card {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.2rem 1.8rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-subtle);
  position: relative;
}

.quote-mark {
  font-family: var(--font-serif);
  font-size: 2.8rem;
  line-height: 1;
  color: var(--color-copper-light);
  margin-bottom: 0.5rem;
  opacity: 0.6;
}

.testimonial-quote {
  font-family: var(--font-serif);
  font-size: 1.02rem;
  line-height: 1.72;
  color: var(--color-plum-deep);
  margin-bottom: 1.6rem;
  font-style: italic;
}

.testimonial-author {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1.1rem;
  border-top: 1px dashed var(--color-border);
}

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

.author-name {
  font-weight: 600;
  font-size: 0.88rem;
  color: var(--color-plum-deep);
}

.author-role {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.testimonial-tag {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--color-copper-dark);
  background-color: var(--color-copper-soft);
  padding: 0.18rem 0.5rem;
  border-radius: var(--radius-sm);
}

/* ==========================================================================
   FAQ Section (Accessible Accordion)
   ========================================================================== */
.faq-accordion {
  max-width: 860px;
  margin-left: auto;
  margin-right: auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background-color: var(--color-ivory-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

.faq-item:hover {
  border-color: var(--color-border-copper);
}

.faq-trigger {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 1.4rem 1.8rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-family: var(--font-serif);
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--color-plum-deep);
}

.faq-trigger:focus-visible {
  outline: 2px solid var(--color-copper);
  outline-offset: -2px;
}

.faq-icon {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background-color: var(--color-ivory-subtle);
  color: var(--color-plum-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: transform var(--transition-normal);
  font-family: var(--font-mono);
  font-size: 0.95rem;
  font-weight: bold;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  background-color: var(--color-copper-soft);
  color: var(--color-copper-dark);
}

.faq-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s cubic-bezier(0.16, 1, 0.3, 1), padding 0.35s ease;
  padding: 0 1.8rem;
}

.faq-item.active .faq-content {
  max-height: 500px;
  padding: 0 1.8rem 1.6rem;
}

.faq-content p {
  font-size: 0.96rem;
  line-height: 1.74;
  color: var(--color-text-body);
}

/* ==========================================================================
   Editorial Footer
   ========================================================================== */
.site-footer {
  background-color: #200E1E;
  color: #ECE5DE;
  padding: 4.8rem 1.5rem 2.5rem;
  margin-top: auto;
  border-top: 2px solid var(--color-copper);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 3rem;
  margin-bottom: 3.5rem;
}

.footer-brand h4 {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  color: #FFFFFF;
  margin-bottom: 0.85rem;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: #BDB0BC;
  margin-bottom: 1.4rem;
}

.footer-heading {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-copper-light);
  margin-bottom: 1.2rem;
}

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

.footer-links a {
  font-size: 0.88rem;
  color: #D3CAD1;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: #FFFFFF;
}

/* External PBN Dofollow Recommendation Links */
.footer-recs a {
  color: #E29B85;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.footer-recs a:hover {
  color: #FFBFA8;
  text-decoration: underline;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.82rem;
  color: #9C8E9A;
  font-family: var(--font-mono);
}

/* ==========================================================================
   Article & Content Pages (tutorial, about, terms, privacy, articles)
   ========================================================================== */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.82rem;
  font-family: var(--font-mono);
  margin-bottom: 2rem;
  color: var(--color-text-muted);
}

.breadcrumbs a {
  color: var(--color-plum-primary);
}

.breadcrumbs a:hover {
  color: var(--color-copper);
}

.breadcrumbs .sep {
  color: var(--color-border);
}

.article-header {
  margin-bottom: 2.8rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border);
}

.article-header h1 {
  margin-bottom: 1.2rem;
}

.article-meta-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.85rem;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
}

.article-body {
  font-size: 1.04rem;
  line-height: 1.82;
  color: var(--color-text-body);
}

.article-body h2 {
  margin-top: 2.6rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-border-subtle);
}

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

.article-body ul, 
.article-body ol {
  margin-left: 1.4rem;
  margin-bottom: 1.4rem;
}

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

.article-callout {
  background-color: var(--color-ivory-subtle);
  border-left: 4px solid var(--color-copper);
  padding: 1.4rem 1.6rem;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 1.8rem 0;
}

.article-callout h4 {
  font-size: 1.05rem;
  color: var(--color-plum-deep);
  margin-bottom: 0.45rem;
}

.article-table-wrap {
  overflow-x: auto;
  margin: 2rem 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.article-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  background-color: var(--color-ivory-surface);
}

.article-table th,
.article-table td {
  padding: 0.85rem 1.2rem;
  border-bottom: 1px solid var(--color-border-subtle);
  text-align: left;
}

.article-table th {
  background-color: var(--color-ivory-subtle);
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--color-plum-deep);
}

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

/* Related Articles Block */
.related-articles {
  margin-top: 4rem;
  padding-top: 2.8rem;
  border-top: 2px solid var(--color-border);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
  margin-top: 1.6rem;
}

/* ==========================================================================
   Responsive Breakpoints: 1024px, 768px, 430px, 390px, 375px
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }

  .hero-stage {
    order: -1;
  }

  .telemetry-board {
    max-width: 100%;
    transform: none;
  }

  .telemetry-board:hover {
    transform: none;
  }

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

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

  .scenarios-split {
    grid-template-columns: 1fr;
  }

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

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

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

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

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

@media (max-width: 768px) {
  :root {
    --section-padding: 4rem 1.25rem;
  }

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

  .hamburger-btn {
    display: block;
  }

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

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

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

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

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

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .adv-features-list {
    grid-template-columns: 1fr;
  }

  .adv-featured-card {
    padding: 2.2rem 1.6rem;
  }
}

@media (max-width: 430px) {
  html {
    font-size: 15px;
  }

  .hero-title {
    font-size: 2.1rem;
  }

  .orbital-viewport {
    width: 230px;
    height: 230px;
  }

  .ring-outer {
    width: 220px;
    height: 220px;
  }

  .ring-mid {
    width: 150px;
    height: 150px;
  }

  .ring-inner {
    width: 90px;
    height: 90px;
  }

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

  .pricing-card {
    padding: 2rem 1.4rem;
  }
}

/* Reduced Motion Override */
@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;
  }

  .ring-outer,
  .ring-mid,
  .ring-inner {
    animation: none !important;
  }

  .telemetry-board {
    transform: none !important;
  }
}