/* ==========================================================================
   可可云 (KeKeyun) - 2026 官方网站设计系统
   DESIGN: Three-dimensional ribbon paths
   COLORS:
     - Pure White: #FFFFFF
     - Dark Petrol: #244852
     - Muted Coral: #C68E7C
     - Pale Sand: #F2EDE6
   TYPOGRAPHY:
     - Headings: Chinese serif fallback
     - Body: Humanist system sans-serif (17px)
     - Region Tags / Badges: Monospace
     - H1: 57px desktop / 36px mobile
   ========================================================================== */

:root {
  --color-white: #FFFFFF;
  --color-dark-petrol: #244852;
  --color-dark-petrol-deep: #162E35;
  --color-dark-petrol-light: #34606C;
  --color-muted-coral: #C68E7C;
  --color-coral-light: #DEABA0;
  --color-coral-soft: #F5EAE6;
  --color-pale-sand: #F2EDE6;
  --color-sand-tint: #E8E2D8;
  --color-sand-card: #FAF7F2;
  --color-text-main: #244852;
  --color-text-muted: #566E74;
  --color-border: rgba(36, 72, 82, 0.14);
  --color-border-subtle: rgba(36, 72, 82, 0.08);

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

  --h1-desktop: 57px;
  --h1-mobile: 36px;
  --body-font-size: 17px;
  --body-line-height: 1.68;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(36, 72, 82, 0.06);
  --shadow-md: 0 8px 24px rgba(36, 72, 82, 0.08);
  --shadow-lg: 0 16px 40px rgba(36, 72, 82, 0.12);
  --shadow-coral: 0 8px 24px rgba(198, 142, 124, 0.25);

  --container-max: 1200px;
  --transition-normal: 0.25s ease;
}

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

html {
  font-size: 17px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--body-font-size);
  line-height: var(--body-line-height);
  color: var(--color-text-main);
  background-color: var(--color-pale-sand);
  background-image: 
    radial-gradient(ellipse at 15% 15%, rgba(198, 142, 124, 0.06) 0%, transparent 60%),
    radial-gradient(ellipse at 85% 75%, rgba(36, 72, 82, 0.05) 0%, transparent 55%);
  min-height: 100vh;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* Headings Fallback */
h1, h2, h3, h4, .serif-heading {
  font-family: var(--font-serif);
  color: var(--color-dark-petrol);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

h1 {
  font-size: var(--h1-desktop);
  line-height: 1.15;
  margin-bottom: 20px;
}

h2 {
  font-size: 34px;
  line-height: 1.25;
  margin-bottom: 14px;
}

h3 {
  font-size: 22px;
  line-height: 1.35;
  margin-bottom: 10px;
}

p {
  margin-bottom: 16px;
  color: var(--color-text-muted);
}

a {
  color: var(--color-dark-petrol);
  text-decoration: none;
  transition: color var(--transition-normal);
}

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

img, svg {
  max-width: 100%;
  display: block;
}

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

/* Section Spacing */
section {
  padding-top: 88px;
  padding-bottom: 88px;
  position: relative;
}

/* Monospace Region Tags & Badges */
.badge-mono {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background-color: var(--color-white);
  color: var(--color-dark-petrol);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  margin-bottom: 16px;
}

.badge-mono.coral {
  background-color: var(--color-coral-soft);
  color: var(--color-dark-petrol);
  border-color: rgba(198, 142, 124, 0.4);
}

.badge-mono .pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-muted-coral);
  display: inline-block;
  box-shadow: 0 0 0 3px rgba(198, 142, 124, 0.2);
}

/* Section Header Typography */
.section-header {
  text-align: center;
  max-width: 760px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 56px;
}

.section-header h2 {
  font-size: 38px;
}

.section-header p {
  font-size: 18px;
  line-height: 1.6;
}

/* ==========================================================================
   Buttons & CTA System
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 600;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition-normal);
  text-align: center;
  line-height: 1.2;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--color-dark-petrol);
  color: var(--color-white);
  border-color: var(--color-dark-petrol);
  box-shadow: 0 4px 14px rgba(36, 72, 82, 0.22);
}

.btn-primary:hover {
  background-color: var(--color-dark-petrol-deep);
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(36, 72, 82, 0.3);
}

.btn-coral {
  background-color: var(--color-muted-coral);
  color: var(--color-white);
  border-color: var(--color-muted-coral);
  box-shadow: var(--shadow-coral);
}

.btn-coral:hover {
  background-color: #B57D6B;
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(181, 125, 107, 0.35);
}

.btn-secondary {
  background-color: var(--color-white);
  color: var(--color-dark-petrol);
  border-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--color-sand-card);
  color: var(--color-dark-petrol);
  border-color: var(--color-dark-petrol);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 9px 18px;
  font-size: 14px;
  border-radius: var(--radius-sm);
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(242, 237, 230, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: background-color var(--transition-normal);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 800;
  color: var(--color-dark-petrol);
}

.brand-logo svg {
  width: 38px;
  height: 38px;
  flex-shrink: 0;
}

.brand-logo .brand-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  background-color: var(--color-dark-petrol);
  color: var(--color-pale-sand);
  padding: 2px 7px;
  border-radius: 4px;
  letter-spacing: 0.05em;
  font-weight: 500;
}

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

.desktop-nav .nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text-main);
  padding: 6px 0;
  position: relative;
}

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

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

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

.mobile-menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-dark-petrol);
  cursor: pointer;
  background-color: var(--color-white);
}

.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 76px;
  left: 0;
  right: 0;
  background-color: var(--color-white);
  border-bottom: 2px solid var(--color-dark-petrol);
  padding: 24px;
  box-shadow: var(--shadow-lg);
  z-index: 999;
}

.mobile-nav-drawer.open {
  display: block;
  animation: slideDown 0.25s ease-out;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

.mobile-nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.mobile-nav-links a {
  font-size: 17px;
  font-weight: 600;
  display: block;
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border-subtle);
}

/* ==========================================================================
   Hero Section with 3D Ribbon Paths & Dashboard
   ========================================================================== */
.hero-section {
  padding-top: 64px;
  padding-bottom: 96px;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 48px;
  align-items: center;
}

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

.hero-title {
  margin-top: 8px;
  margin-bottom: 22px;
  color: var(--color-dark-petrol);
}

.hero-intro {
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-text-muted);
  margin-bottom: 32px;
}

.hero-badges-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.hero-badge-item {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-dark-petrol);
  background-color: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--color-border);
  padding: 4px 10px;
  border-radius: 4px;
}

/* Hero Dashboard 3D Space */
.hero-dashboard-wrapper {
  perspective: 1200px;
  position: relative;
}

.hero-dashboard-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-lg);
  padding: 28px;
  position: relative;
  overflow: hidden;
}

.dashboard-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 20px;
}

.dashboard-title-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.dashboard-title-group .indicator {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background-color: #2BA878;
  box-shadow: 0 0 0 3px rgba(43, 168, 120, 0.2);
}

.dashboard-title {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--color-dark-petrol);
}

.dashboard-tag-mono {
  font-family: var(--font-mono);
  font-size: 11px;
  background-color: var(--color-pale-sand);
  color: var(--color-dark-petrol);
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 600;
}

/* 3D Ribbon Stage */
.ribbon-stage {
  position: relative;
  width: 100%;
  height: 330px;
  transform-style: preserve-3d;
}

/* Ribbon SVG Container animated in 3D */
.ribbon-3d-canvas {
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  animation: ribbonDepthCycle 16s ease-in-out infinite;
  transform-origin: center center;
}

[data-animating="false"] .ribbon-3d-canvas {
  animation-play-state: paused;
}

@keyframes ribbonDepthCycle {
  0% {
    transform: perspective(1000px) rotateY(0deg) translateZ(0px);
  }
  25% {
    transform: perspective(1000px) rotateY(3.5deg) translateZ(12px);
  }
  50% {
    transform: perspective(1000px) rotateY(0deg) translateZ(24px);
  }
  75% {
    transform: perspective(1000px) rotateY(-3.5deg) translateZ(12px);
  }
  100% {
    transform: perspective(1000px) rotateY(0deg) translateZ(0px);
  }
}

/* Stable Planar Region Labels (Fixed & Readable) */
.region-node-badge {
  position: absolute;
  z-index: 10;
  background: var(--color-white);
  border: 1.5px solid var(--color-dark-petrol);
  border-radius: 6px;
  padding: 6px 12px;
  box-shadow: 0 4px 12px rgba(36, 72, 82, 0.12);
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--color-dark-petrol);
  pointer-events: auto;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.region-node-badge:hover {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 6px 18px rgba(36, 72, 82, 0.2);
  border-color: var(--color-muted-coral);
}

.region-node-badge .node-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--color-dark-petrol);
}

.region-node-badge.coral-node .node-dot {
  background: var(--color-muted-coral);
}

.region-node-badge .node-state {
  font-size: 11px;
  color: var(--color-text-muted);
  font-weight: normal;
}

/* Individual node placements */
.node-hk { top: 22px; left: 18px; }
.node-jp { top: 38px; right: 24px; }
.node-sg { bottom: 32px; left: 32px; }
.node-us { bottom: 48px; right: 28px; }

/* Dashboard Footer Meta */
.dashboard-footer-meta {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text-muted);
}

.dashboard-footer-meta .meta-highlight {
  color: var(--color-dark-petrol);
  font-weight: 600;
}

/* ==========================================================================
   Advantages Section: Three Distinct Ribbon Paths
   ========================================================================== */
.advantages-section {
  background-color: var(--color-sand-card);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.ribbon-paths-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  align-items: stretch;
}

/* Path 1: Undulating S-Curve Ribbon Card */
.path-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  padding: 36px 30px;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.path-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-dark-petrol);
}

.path-card-1 {
  border-top: 5px solid var(--color-dark-petrol);
}

.path-card-2 {
  border-top: 5px solid var(--color-muted-coral);
}

.path-card-3 {
  border-top: 5px solid var(--color-dark-petrol-light);
}

.path-ribbon-visual {
  width: 100%;
  height: 90px;
  margin-bottom: 24px;
  position: relative;
}

.path-ribbon-visual svg {
  width: 100%;
  height: 100%;
  overflow: visible;
}

.path-card .card-step-mono {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--color-muted-coral);
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.path-card h3 {
  font-size: 23px;
  margin-bottom: 14px;
  color: var(--color-dark-petrol);
}

.path-card p {
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text-muted);
  flex-grow: 1;
}

.path-features-list {
  list-style: none;
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px dashed var(--color-border);
  display: flex;
  flex-direction: column;
  gap: 9px;
  font-size: 14px;
  color: var(--color-dark-petrol);
  font-weight: 500;
}

.path-features-list li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.path-features-list li::before {
  content: "—";
  color: var(--color-muted-coral);
  font-weight: bold;
}

/* ==========================================================================
   Global Nodes: Horizontal Itinerary Ribbon Track
   ========================================================================== */
.nodes-section {
  position: relative;
}

.itinerary-track-container {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  padding: 40px 32px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.itinerary-disclaimer {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-text-muted);
  background-color: var(--color-pale-sand);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 10px 16px;
  margin-bottom: 32px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.itinerary-disclaimer span.icon {
  font-weight: bold;
  color: var(--color-dark-petrol);
}

/* Horizontal Itinerary Nodes Flow */
.itinerary-horizontal-flow {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 24px;
  padding-bottom: 12px;
}

.itinerary-step {
  position: relative;
  background: var(--color-sand-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
}

.itinerary-step:hover {
  background: var(--color-white);
  border-color: var(--color-dark-petrol);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.itinerary-step-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.itinerary-code {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 800;
  color: var(--color-dark-petrol);
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  padding: 4px 8px;
  border-radius: 4px;
}

.itinerary-seq {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-muted-coral);
  font-weight: 700;
}

.itinerary-step h4 {
  font-family: var(--font-serif);
  font-size: 19px;
  margin-bottom: 8px;
  color: var(--color-dark-petrol);
}

.itinerary-step p {
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 12px;
  color: var(--color-text-muted);
}

.itinerary-tags {
  margin-top: auto;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.itinerary-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  background-color: var(--color-white);
  border: 1px solid var(--color-border-subtle);
  padding: 2px 6px;
  border-radius: 3px;
  color: var(--color-dark-petrol);
}

/* Connecting Line across Steps in Desktop */
.itinerary-track-svg {
  width: 100%;
  height: 36px;
  margin-bottom: 16px;
}

/* ==========================================================================
   AI Scenario Full-Width Distinct Layout
   ========================================================================== */
.ai-section {
  background: var(--color-dark-petrol);
  color: var(--color-pale-sand);
  padding-top: 96px;
  padding-bottom: 96px;
  position: relative;
  overflow: hidden;
}

.ai-section::before {
  content: "";
  position: absolute;
  top: -100px;
  right: -100px;
  width: 450px;
  height: 450px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(198, 142, 124, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

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

.ai-section .section-header p {
  color: rgba(242, 237, 230, 0.8);
}

.ai-section .badge-mono {
  background: rgba(255, 255, 255, 0.1);
  color: var(--color-pale-sand);
  border-color: rgba(255, 255, 255, 0.2);
}

.ai-section .badge-mono .pulse-dot {
  background: var(--color-coral-light);
}

/* Full-Width AI Bento Grid */
.ai-bento-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  grid-template-rows: auto auto;
  gap: 24px;
}

.ai-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  padding: 32px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: transform var(--transition-normal), border-color var(--transition-normal);
}

.ai-card:hover {
  border-color: var(--color-muted-coral);
  transform: translateY(-2px);
}

.ai-card-primary {
  grid-row: span 2;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.ai-card h3 {
  color: var(--color-white);
  font-size: 26px;
  margin-bottom: 12px;
}

.ai-card p {
  color: rgba(242, 237, 230, 0.8);
  font-size: 16px;
}

.ai-tools-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.ai-tool-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-pale-sand);
  transition: background var(--transition-normal);
}

.ai-tool-chip:hover {
  background: rgba(198, 142, 124, 0.25);
  border-color: var(--color-muted-coral);
}

.ai-tool-chip .chip-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-coral-light);
}

.ai-metrics-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.ai-metric-item {
  font-family: var(--font-mono);
}

.ai-metric-item .metric-label {
  font-size: 12px;
  color: rgba(242, 237, 230, 0.6);
  text-transform: uppercase;
}

.ai-metric-item .metric-val {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-coral-light);
  margin-top: 4px;
}

/* ==========================================================================
   Streaming Scenario Full-Width Distinct Panoramic Layout
   ========================================================================== */
.streaming-section {
  background-color: var(--color-pale-sand);
  padding-top: 96px;
  padding-bottom: 96px;
  position: relative;
}

.streaming-theater-container {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-md);
  padding: 44px;
  position: relative;
  overflow: hidden;
}

.streaming-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 18px;
  margin-top: 36px;
}

.streaming-platform-card {
  background: var(--color-sand-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px 18px;
  text-align: center;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
}

.streaming-platform-card:hover {
  background: var(--color-white);
  border-color: var(--color-muted-coral);
  transform: translateY(-4px);
  box-shadow: var(--shadow-sm);
}

.streaming-badge-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-muted-coral);
  font-weight: 700;
  margin-bottom: 10px;
}

.streaming-platform-card h4 {
  font-family: var(--font-serif);
  font-size: 18px;
  color: var(--color-dark-petrol);
  margin-bottom: 6px;
}

.streaming-platform-card p {
  font-size: 13px;
  color: var(--color-text-muted);
  line-height: 1.5;
  margin-bottom: 12px;
}

.streaming-quality-pill {
  font-family: var(--font-mono);
  font-size: 11px;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  padding: 3px 8px;
  border-radius: 4px;
  color: var(--color-dark-petrol);
  font-weight: 600;
  margin-top: auto;
}

/* Streaming Architecture Feature Strip */
.streaming-feature-strip {
  margin-top: 36px;
  padding-top: 28px;
  border-top: 1px solid var(--color-border);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.strip-item h4 {
  font-size: 17px;
  margin-bottom: 6px;
  color: var(--color-dark-petrol);
}

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

/* ==========================================================================
   Pricing Section: Stable Flat Surfaces (4–5 Tiers, exactly 1 推荐套餐)
   ========================================================================== */
.pricing-section {
  background: var(--color-sand-card);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

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

.pricing-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

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

/* Exactly One 推荐套餐 */
.pricing-card.featured {
  border: 2px solid var(--color-muted-coral);
  box-shadow: var(--shadow-coral);
  background: #FFFDFC;
  transform: scale(1.02);
  z-index: 2;
}

.pricing-card.featured:hover {
  transform: scale(1.02) translateY(-4px);
}

.featured-ribbon-tag {
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-muted-coral);
  color: var(--color-white);
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  box-shadow: 0 2px 8px rgba(198, 142, 124, 0.4);
}

.pricing-tier-name {
  font-family: var(--font-serif);
  font-size: 22px;
  color: var(--color-dark-petrol);
  margin-bottom: 8px;
}

.pricing-desc {
  font-size: 14px;
  color: var(--color-text-muted);
  min-height: 42px;
  margin-bottom: 18px;
}

.pricing-price-box {
  margin-bottom: 22px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--color-border);
}

.pricing-price-box .price-num {
  font-family: var(--font-mono);
  font-size: 38px;
  font-weight: 800;
  color: var(--color-dark-petrol);
  line-height: 1;
}

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

.pricing-price-box .billing-cycle {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-muted-coral);
  margin-top: 6px;
  font-weight: 600;
}

.pricing-features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 11px;
  font-size: 14px;
  color: var(--color-dark-petrol);
  margin-bottom: 28px;
  flex-grow: 1;
}

.pricing-features-list li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.45;
}

.pricing-features-list li .check-icon {
  color: var(--color-muted-coral);
  font-weight: bold;
}

.pricing-note {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text-muted);
  text-align: center;
  margin-top: 24px;
}

/* ==========================================================================
   Nine SEO Articles Section (3 / 2 / 1 Desktop / Tablet / Mobile)
   ========================================================================== */
.articles-section {
  position: relative;
}

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

.article-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  padding: 28px;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  position: relative;
}

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

.article-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.article-category {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--color-muted-coral);
  background: var(--color-coral-soft);
  padding: 3px 8px;
  border-radius: 4px;
}

.article-readtime {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text-muted);
}

.article-card h3 {
  font-size: 20px;
  line-height: 1.4;
  margin-bottom: 12px;
}

.article-card h3 a {
  color: var(--color-dark-petrol);
}

.article-card h3 a:hover {
  color: var(--color-muted-coral);
}

.article-card p {
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--color-text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-card-footer {
  margin-top: auto;
  padding-top: 14px;
  border-top: 1px solid var(--color-border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.article-date {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text-muted);
}

.article-card-footer .read-more-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-dark-petrol);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.article-card-footer .read-more-link:hover {
  color: var(--color-muted-coral);
}

/* ==========================================================================
   Testimonials Section (3–6 Sourced / Marked-Sample)
   ========================================================================== */
.testimonials-section {
  background: var(--color-sand-card);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

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

.testimonial-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  padding: 28px;
  display: flex;
  flex-direction: column;
}

.testimonial-scenario-tag {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-muted-coral);
  font-weight: 700;
  margin-bottom: 12px;
}

.testimonial-card blockquote {
  font-size: 15.5px;
  line-height: 1.65;
  color: var(--color-dark-petrol);
  margin-bottom: 20px;
  flex-grow: 1;
}

.testimonial-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 14px;
  border-top: 1px dashed var(--color-border);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text-muted);
}

.testimonial-source-badge {
  background: var(--color-pale-sand);
  border: 1px solid var(--color-border);
  padding: 2px 7px;
  border-radius: 4px;
  font-size: 11px;
}

/* ==========================================================================
   FAQ Section: Native Accessible Accordion
   ========================================================================== */
.faq-section {
  position: relative;
}

.faq-container {
  max-width: 860px;
  margin-left: auto;
  margin-right: auto;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--color-white);
  border-radius: var(--radius-md);
  border: 1.5px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: border-color var(--transition-normal);
}

.faq-item.active {
  border-color: var(--color-dark-petrol);
}

.faq-question-btn {
  width: 100%;
  background: none;
  border: none;
  padding: 22px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  text-align: left;
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-dark-petrol);
  gap: 16px;
}

.faq-question-btn:hover {
  color: var(--color-muted-coral);
}

.faq-icon {
  font-size: 20px;
  font-family: var(--font-mono);
  transition: transform var(--transition-normal);
  color: var(--color-muted-coral);
  flex-shrink: 0;
}

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

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease-out;
  padding: 0 24px;
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text-muted);
}

.faq-item.active .faq-answer {
  max-height: 600px;
  padding-bottom: 22px;
}

/* ==========================================================================
   Footer Section
   ========================================================================== */
.site-footer {
  background-color: var(--color-dark-petrol);
  color: var(--color-pale-sand);
  padding-top: 72px;
  padding-bottom: 40px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-top-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-brand h3 {
  color: var(--color-white);
  font-size: 24px;
  margin-bottom: 12px;
}

.footer-brand p {
  color: rgba(242, 237, 230, 0.75);
  font-size: 15px;
  line-height: 1.6;
  max-width: 320px;
}

.footer-col h4 {
  font-family: var(--font-serif);
  color: var(--color-white);
  font-size: 17px;
  margin-bottom: 18px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: rgba(242, 237, 230, 0.75);
  font-size: 15px;
  transition: color var(--transition-normal);
}

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

/* Recommended External Sourced Guides Area */
.footer-external-guides {
  padding-top: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-guides-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-size: 14px;
}

.footer-guides-title {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-coral-light);
  font-weight: 700;
  letter-spacing: 0.04em;
}

.footer-guides-links {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
}

.footer-guide-link {
  color: var(--color-pale-sand);
  font-size: 14.5px;
  font-weight: 500;
  border-bottom: 1px dashed rgba(242, 237, 230, 0.4);
  padding-bottom: 2px;
  transition: all var(--transition-normal);
}

.footer-guide-link:hover {
  color: var(--color-coral-light);
  border-bottom-color: var(--color-coral-light);
}

/* Footer Bottom Bar */
.footer-bottom {
  padding-top: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13.5px;
  color: rgba(242, 237, 230, 0.6);
  font-family: var(--font-mono);
}

.footer-bottom-links {
  display: flex;
  gap: 20px;
}

.footer-bottom-links a {
  color: rgba(242, 237, 230, 0.6);
}

.footer-bottom-links a:hover {
  color: var(--color-pale-sand);
}

/* ==========================================================================
   Article Pages Template Layout & Breadcrumb
   ========================================================================== */
.article-page-layout {
  padding-top: 48px;
  padding-bottom: 80px;
}

.article-main-container {
  max-width: 860px;
  margin-left: auto;
  margin-right: auto;
  background: var(--color-white);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 48px 44px;
  box-shadow: var(--shadow-sm);
}

.breadcrumb-nav {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-text-muted);
  margin-bottom: 24px;
}

.breadcrumb-nav a {
  color: var(--color-dark-petrol);
}

.breadcrumb-nav a:hover {
  color: var(--color-muted-coral);
}

.article-meta-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.article-meta-header h1 {
  font-size: 40px;
  line-height: 1.25;
  margin-top: 12px;
  margin-bottom: 16px;
}

.article-meta-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-text-muted);
}

.article-body-content {
  font-size: 17px;
  line-height: 1.8;
  color: #2F3E46;
}

.article-body-content h2 {
  font-size: 27px;
  margin-top: 40px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border-subtle);
  color: var(--color-dark-petrol);
}

.article-body-content h3 {
  font-size: 21px;
  margin-top: 28px;
  margin-bottom: 12px;
  color: var(--color-dark-petrol);
}

.article-body-content p {
  margin-bottom: 18px;
  color: #37474F;
}

.article-body-content ul, .article-body-content ol {
  margin-left: 24px;
  margin-bottom: 20px;
}

.article-body-content li {
  margin-bottom: 8px;
  color: #37474F;
}

.article-table-wrapper {
  overflow-x: auto;
  margin: 28px 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.article-body-content table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 15px;
}

.article-body-content th {
  background-color: var(--color-pale-sand);
  color: var(--color-dark-petrol);
  font-weight: 700;
  padding: 12px 16px;
  border-bottom: 1.5px solid var(--color-border);
  font-family: var(--font-sans);
}

.article-body-content td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border-subtle);
  color: #37474F;
}

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

.article-callout {
  background: var(--color-sand-card);
  border-left: 4px solid var(--color-muted-coral);
  border-radius: var(--radius-sm);
  padding: 18px 22px;
  margin: 24px 0;
  font-size: 15.5px;
}

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

.related-articles-section {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 2px solid var(--color-border);
}

.related-articles-section h3 {
  font-size: 22px;
  margin-bottom: 20px;
}

.related-links-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.related-article-card {
  background: var(--color-sand-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  transition: all var(--transition-normal);
}

.related-article-card:hover {
  background: var(--color-white);
  border-color: var(--color-dark-petrol);
  transform: translateY(-2px);
}

.related-article-card h4 {
  font-size: 16px;
  margin-bottom: 6px;
  color: var(--color-dark-petrol);
}

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

/* ==========================================================================
   Static Pages Template Layout (About, Terms, Privacy, Sitemap, Tutorial)
   ========================================================================== */
.static-page-container {
  max-width: 920px;
  margin-left: auto;
  margin-right: auto;
  background: var(--color-white);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 52px 48px;
  box-shadow: var(--shadow-sm);
  margin-top: 48px;
  margin-bottom: 80px;
}

.static-page-header {
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.static-page-header h1 {
  font-size: 42px;
  margin-bottom: 12px;
}

.static-page-content {
  font-size: 16.5px;
  line-height: 1.8;
  color: #2F3E46;
}

.static-page-content h2 {
  font-size: 26px;
  margin-top: 36px;
  margin-bottom: 16px;
  color: var(--color-dark-petrol);
}

.static-page-content h3 {
  font-size: 20px;
  margin-top: 24px;
  margin-bottom: 12px;
  color: var(--color-dark-petrol);
}

.static-page-content p {
  margin-bottom: 16px;
  color: #37474F;
}

.static-page-content ul, .static-page-content ol {
  margin-left: 24px;
  margin-bottom: 20px;
}

.static-page-content li {
  margin-bottom: 8px;
}

/* Sitemap Directory Index */
.sitemap-group-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 28px;
}

.sitemap-group {
  background: var(--color-sand-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
}

.sitemap-group h3 {
  font-size: 20px;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 10px;
  margin-bottom: 16px;
}

.sitemap-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sitemap-list a {
  font-size: 15px;
  color: var(--color-dark-petrol);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.sitemap-list a:hover {
  color: var(--color-muted-coral);
}

.sitemap-list a::before {
  content: "→";
  color: var(--color-muted-coral);
  font-family: var(--font-mono);
}

/* ==========================================================================
   Responsive Breakpoints: 1440px, 1024px, 768px, 430px, 390px, 375px
   ========================================================================== */
@media (max-width: 1440px) {
  .container {
    max-width: 1160px;
  }
}

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-content {
    max-width: 100%;
    text-align: left;
  }

  .ribbon-paths-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

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

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

  .ai-card-primary {
    grid-row: auto;
  }

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

  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

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

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

  /* Articles 2 Columns on Tablet */
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

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

  .footer-top-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

@media (max-width: 768px) {
  h1 {
    font-size: var(--h1-mobile);
    line-height: 1.2;
  }

  h2, .section-header h2 {
    font-size: 28px;
  }

  section {
    padding-top: 64px;
    padding-bottom: 64px;
  }

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

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

  .ribbon-stage {
    height: 280px;
  }

  .itinerary-horizontal-flow {
    grid-template-columns: 1fr;
  }

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

  .streaming-feature-strip {
    grid-template-columns: 1fr;
    gap: 18px;
  }

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

  /* Articles 1 Column on Mobile */
  .articles-grid {
    grid-template-columns: 1fr;
  }

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

  .footer-top-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-guides-row {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }

  .article-main-container, .static-page-container {
    padding: 32px 20px;
  }

  .related-links-grid, .sitemap-group-grid {
    grid-template-columns: 1fr;
  }
}

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

  h1 {
    font-size: 33px;
  }

  .btn {
    width: 100%;
    padding: 13px 20px;
  }

  .hero-dashboard-card {
    padding: 18px;
  }

  .ribbon-stage {
    height: 250px;
  }

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

  .ai-metrics-row {
    grid-template-columns: 1fr;
    gap: 12px;
  }
}

@media (max-width: 390px) {
  h1 {
    font-size: 30px;
  }

  .brand-logo span {
    font-size: 19px;
  }

  .path-card, .pricing-card, .article-card {
    padding: 22px 18px;
  }
}

@media (max-width: 375px) {
  h1 {
    font-size: 28px;
  }

  .badge-mono {
    font-size: 11px;
    padding: 5px 10px;
  }

  .btn-sm {
    padding: 8px 14px;
    font-size: 13px;
  }
}

/* ==========================================================================
   Reduced Motion Accessibility Preference
   ========================================================================== */
@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;
  }

  .ribbon-3d-canvas {
    animation: none !important;
    transform: none !important;
  }

  .hero-dashboard-wrapper {
    perspective: none !important;
  }
}