/* ==========================================================================
   INTERACTIVE LONGFORM: HẠ TẦNG SỐ HÀ NỘI
   Modern Data Journalism Editorial System (Light Theme - Báo chí Hiện Đại)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400&family=Outfit:wght@400;500;600;700;800;900&family=Space+Grotesk:wght@500;700&display=swap');

:root {
  /* Light Theme Color Palette */
  --bg-primary: #f8fafc;
  /* Crisp editorial off-white */
  --bg-surface: #ffffff;
  /* Pure white for primary cards */
  --bg-card: #ffffff;
  --bg-card-subtle: #f1f5f9;
  /* Light slate fill for nested blocks */
  --bg-card-hover: #f8fafc;
  --bg-card-glass: rgba(255, 255, 255, 0.88);
  --bg-glass-heavy: rgba(255, 255, 255, 0.94);

  /* Text & Typography Colors */
  --text-main: #0f172a;
  /* Slate 900 - maximum readability */
  --text-secondary: #334155;
  /* Slate 700 - rich editorial body text */
  --text-muted: #04234f;
  /* Slate 500 */
  --text-dim: #94a3b8;
  /* Slate 400 */

  /* Modern Editorial Accents */
  --cyan-bright: #0284c7;
  /* Refined Sky 600 for light mode */
  --cyan-glow: rgba(2, 132, 199, 0.15);
  --blue-brand: #2563eb;
  /* Blue 600 */
  --blue-deep: #1d4ed8;
  --emerald-accent: #059669;
  /* Emerald 600 */
  --emerald-glow: rgba(5, 150, 105, 0.15);
  --amber-accent: #d97706;
  /* Amber 600 */
  --amber-glow: rgba(217, 119, 6, 0.15);
  --purple-accent: #7c3aed;

  /* Borders */
  --border-subtle: rgba(15, 23, 42, 0.08);
  --border-medium: rgba(15, 23, 42, 0.15);
  --border-glow-cyan: rgba(2, 132, 199, 0.28);
  --border-glow-blue: rgba(37, 99, 235, 0.25);

  /* Typography Variables */
  --font-body: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Outfit', 'Be Vietnam Pro', sans-serif;
  --font-mono: 'Space Grotesk', monospace;

  /* Sizing Constraints */
  --content-max-width: 780px;
  --infographic-max-width: 1140px;
  --full-bleed-max-width: 1360px;

  /* Radii & Shadows */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-ambient: 0 16px 36px -12px rgba(15, 23, 42, 0.08);
  --shadow-cyan-glow: 0 12px 28px -6px rgba(2, 132, 199, 0.12);
  --shadow-card: 0 10px 25px -8px rgba(15, 23, 42, 0.06), 0 2px 6px -1px rgba(15, 23, 42, 0.04);

  /* Smooth transitions */
  --transition-smooth: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-snappy: all 0.2s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-primary);
  color: var(--text-main);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: 18px;
  /* Strict minimum 16px, 18px for editorial luxury */
  line-height: 1.85;
  font-weight: 400;
  color: var(--text-secondary);
  background-color: var(--bg-primary);
  overflow-x: hidden;
  position: relative;
}

/* Subtle modern mesh in light mode */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background:
    radial-gradient(circle at 12% 18%, rgba(2, 132, 199, 0.035) 0%, transparent 45%),
    radial-gradient(circle at 88% 65%, rgba(37, 99, 235, 0.03) 0%, transparent 45%),
    radial-gradient(circle at 50% 90%, rgba(5, 150, 105, 0.025) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

/* Top Reading Progress Bar */
.reading-progress-track {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: rgba(15, 23, 42, 0.06);
  z-index: 1000;
}

.reading-progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #0284c7, #2563eb, #059669);
  box-shadow: 0 0 10px rgba(2, 132, 199, 0.6);
  transition: width 0.1s linear;
}

/* Minimalist Unobtrusive Floating Reading Tracker */
.reading-tracker {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 900;
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-glass-heavy);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-full);
  padding: 6px 14px;
  box-shadow: var(--shadow-ambient);
  transition: var(--transition-smooth);
}

.reading-tracker:hover {
  border-color: var(--cyan-bright);
  box-shadow: 0 8px 24px rgba(2, 132, 199, 0.18);
}

.tracker-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan-bright);
  animation: pulseDot 2s infinite ease-in-out;
}

@keyframes pulseDot {

  0%,
  100% {
    opacity: 0.5;
    transform: scale(0.9);
  }

  50% {
    opacity: 1;
    transform: scale(1.2);
    box-shadow: 0 0 8px var(--cyan-bright);
  }
}

.tracker-text {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 600;
  color: var(--text-main);
}

.tracker-pills {
  display: flex;
  gap: 6px;
  margin-left: 6px;
}

.tracker-pill-btn {
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  color: var(--text-muted);
  font-size: 16px;
  font-family: var(--font-mono);
  padding: 2px 10px;
  cursor: pointer;
  transition: var(--transition-snappy);
}

.tracker-pill-btn:hover {
  color: var(--text-main);
  border-color: var(--cyan-bright);
}

.tracker-pill-btn.active {
  background: rgba(2, 132, 199, 0.1);
  border-color: var(--cyan-bright);
  color: var(--cyan-bright);
  font-weight: 700;
}

/* ==========================================================================
   HERO / ARTICLE HEADER (LIGHT EDITORIAL)
   ========================================================================== */
.hero-section {
  position: relative;
  z-index: 1;
  min-height: 90vh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 120px 24px 60px;
  overflow: hidden;
}

.hero-background-wrapper {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  overflow: hidden;
}

.hero-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  filter: brightness(0.9) saturate(1.1);
  transform: scale(1.03);
  transition: transform 0.6s ease-out;
}

.hero-gradient-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg,
      rgba(248, 250, 252, 0.45) 0%,
      rgba(248, 250, 252, 0.88) 55%,
      var(--bg-primary) 100%);
}

.hero-content {
  max-width: 1100px;
  margin: 0 auto;
  width: 100%;
  position: relative;
  z-index: 2;
}

.kicker-tag {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: rgba(2, 132, 199, 0.1);
  border: 1px solid rgba(2, 132, 199, 0.3);
  color: var(--cyan-bright);
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  margin-bottom: 24px;
  backdrop-filter: blur(8px);
}

.kicker-tag::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan-bright);
  box-shadow: 0 0 8px var(--cyan-bright);
}

.article-title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 5.5vw, 4.4rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--text-main);
  margin-bottom: 28px;
  text-shadow: 0 2px 10px rgba(255, 255, 255, 0.8);
}

.article-title span.accent-text {
  background: linear-gradient(120deg, #0284c7 0%, #2563eb 50%, #4338ca 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.article-meta-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
  font-size: 17px;
  color: var(--text-secondary);
  border-top: 1px solid var(--border-medium);
  padding-top: 20px;
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.meta-item svg {
  color: var(--cyan-bright);
}

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

/* ==========================================================================
   SAPO / LEAD SECTION
   ========================================================================== */
.sapo-container {
  max-width: var(--content-max-width);
  margin: 50px auto 40px;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.sapo-box {
  position: relative;
  background: var(--bg-surface);
  border-left: 4px solid var(--cyan-bright);
  border-top: 1px solid var(--border-subtle);
  border-right: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 34px 38px;
  box-shadow: var(--shadow-card);
}

.sapo-text {
  font-size: 21px;
  line-height: 1.8;
  color: var(--text-main);
  font-weight: 600;
  margin-bottom: 16px;
}

.sapo-text:last-child {
  margin-bottom: 0;
  color: var(--text-secondary);
  font-weight: 500;
}

.sapo-text strong {
  color: var(--cyan-bright);
  font-weight: 700;
}

/* ==========================================================================
   EDITORIAL ARTICLE CONTAINER & TYPOGRAPHY
   ========================================================================== */
.article-body-wrapper {
  position: relative;
  z-index: 1;
  padding: 20px 0 100px;
}

.editorial-section {
  position: relative;
  padding: 60px 0;
}

.editorial-section:first-of-type {
  padding-top: 20px;
}

.section-anchor-indicator {
  position: absolute;
  top: -20px;
  left: 0;
  visibility: hidden;
}

/* Text Content Column */
.text-column {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Section Header Badges & Titles */
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  background: rgba(2, 132, 199, 0.08);
  border: 1px solid rgba(2, 132, 199, 0.25);
  padding: 4px 14px;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 3.8vw, 2.75rem);
  font-weight: 800;
  line-height: 1.25;
  color: var(--text-main);
  margin-bottom: 32px;
  letter-spacing: -0.015em;
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 56px;
  height: 4px;
  background: linear-gradient(90deg, var(--cyan-bright), var(--blue-brand));
  border-radius: 2px;
  margin-top: 14px;
}

/* Paragraphs */
.editorial-p {
  font-size: 19px;
  /* Crisp editorial body size */
  line-height: 1.88;
  color: var(--text-secondary);
  margin-bottom: 24px;
  text-align: justify;
}

.editorial-p strong {
  color: var(--text-main);
  font-weight: 700;
}

/* Editorial Dropcap on first paragraph of section */
.has-dropcap::first-letter {
  float: left;
  font-family: var(--font-display);
  font-size: 4.8rem;
  line-height: 0.8;
  padding-top: 6px;
  padding-right: 14px;
  padding-bottom: 4px;
  color: var(--cyan-bright);
  font-weight: 800;
}

/* ==========================================================================
   PHOTO ESSAY / TRANSITION BREAKOUTS
   ========================================================================== */
.photo-breakout {
  max-width: var(--infographic-max-width);
  margin: 50px auto;
  padding: 0 24px;
}

.photo-card {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  box-shadow: var(--shadow-card);
}

.photo-card img {
  width: 100%;
  height: auto;
  max-height: 520px;
  object-fit: cover;
  display: block;
  transition: transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.photo-card:hover img {
  transform: scale(1.02);
}

.photo-caption {
  padding: 16px 24px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  font-size: 16px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 12px;
}

.photo-caption svg {
  color: var(--cyan-bright);
  flex-shrink: 0;
}

/* ==========================================================================
   INFOGRAPHICS SYSTEM - GENERAL RULES (MIN FONT 18PX)
   ========================================================================== */
.infographic-wrapper {
  max-width: var(--infographic-max-width);
  margin: 50px auto 60px;
  padding: 0 24px;
}

.infographic-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-glow-cyan);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-cyan-glow), var(--shadow-ambient);
  position: relative;
  overflow: hidden;
}

/* Strict Infographic font sizing */
.infographic-card,
.infographic-card * {
  /* Enforce min 18px on all descriptive infographic text, labels, badges */
  font-size: 18px;
}

.infographic-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(2, 132, 199, 0.08);
  border: 1px solid rgba(2, 132, 199, 0.25);
  color: var(--cyan-bright);
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  margin-bottom: 14px;
}

.infographic-title {
  font-family: var(--font-display);
  font-size: clamp(22px, 2.6vw, 32px);
  font-weight: 800;
  line-height: 1.3;
  color: var(--text-main);
  margin-bottom: 8px;
}

.infographic-subtitle {
  font-size: 18px;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 30px;
}

/* ==========================================================================
   INFOGRAPHIC 1: HẠ TẦNG KẾT NỐI & TÍNH TOÁN 2026 - 2030 (LIGHT)
   ========================================================================== */
.controls-timeline-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 20px;
  margin-bottom: 32px;
}

.timeline-info-label {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-main);
}

.timeline-toggle-group {
  display: flex;
  gap: 8px;
  background: rgba(15, 23, 42, 0.06);
  padding: 4px;
  border-radius: var(--radius-full);
}

.timeline-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  padding: 8px 24px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: var(--transition-snappy);
}

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

.timeline-btn.active {
  background: var(--cyan-bright);
  color: #ffffff;
  box-shadow: 0 4px 15px rgba(2, 132, 199, 0.35);
}

/* Metric Cards Grid */
.metrics-grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin-bottom: 36px;
}

.metric-data-card {
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: var(--transition-smooth);
}

.metric-data-card:hover {
  border-color: var(--cyan-bright);
  background: #ffffff;
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(2, 132, 199, 0.12);
}

.metric-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.metric-icon-wrap {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(2, 132, 199, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--cyan-bright);
}

.metric-period-pill {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--cyan-bright);
  background: rgba(2, 132, 199, 0.08);
  padding: 2px 10px;
  border-radius: var(--radius-full);
}

.metric-number-display {
  font-family: var(--font-display);
  font-size: 44px;
  font-weight: 800;
  line-height: 1;
  color: var(--text-main);
  margin-bottom: 10px;
  letter-spacing: -0.02em;
}

.metric-number-display span.unit {
  font-size: 26px;
  color: var(--cyan-bright);
  font-weight: 700;
}

.metric-label-title {
  font-size: 18px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.metric-progress-track {
  width: 100%;
  height: 8px;
  background: rgba(15, 23, 42, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.metric-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #0284c7, #2563eb);
  border-radius: var(--radius-full);
  transition: width 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 5G Priority & Core Compute Dual Panels */
.dual-infographic-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.sub-panel {
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
}

.sub-panel-title {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
}

.sub-panel-title svg {
  color: var(--cyan-bright);
}

.chip-tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hotspot-chip {
  background: #ffffff;
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
  transition: var(--transition-snappy);
}

.hotspot-chip:hover {
  background: rgba(2, 132, 199, 0.1);
  border-color: var(--cyan-bright);
  color: var(--cyan-bright);
}

.hotspot-chip svg {
  color: var(--cyan-bright);
  width: 18px;
  height: 18px;
}

.compute-nodes-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.compute-node-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 16px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
  transition: var(--transition-snappy);
}

.compute-node-item:hover {
  border-color: var(--blue-brand);
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.1);
}

.node-icon-box {
  background: rgba(37, 99, 235, 0.1);
  color: #2563eb;
  border-radius: 8px;
  padding: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.node-content-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 4px;
}

.node-content-desc {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ==========================================================================
   INFOGRAPHIC 2: KIẾN TRÚC HỆ ĐIỀU HÀNH SỐ (LIGHT)
   ========================================================================== */
.infographic-card.theme-emerald {
  border-color: rgba(5, 150, 105, 0.35);
  box-shadow: 0 12px 28px -6px rgba(5, 150, 105, 0.12), var(--shadow-ambient);
}

.infographic-badge.badge-emerald {
  background: rgba(5, 150, 105, 0.08);
  border-color: rgba(5, 150, 105, 0.25);
  color: var(--emerald-accent);
}

.data-ecosystem-flow {
  display: flex;
  flex-direction: column;
  gap: 28px;
  margin-bottom: 32px;
}

.flow-layer-card {
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: var(--transition-smooth);
}

.flow-layer-card:hover {
  border-color: var(--emerald-accent);
}

.layer-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 12px;
}

.layer-title-text {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
}

.layer-title-text svg {
  color: var(--emerald-accent);
}

.layer-badge-desc {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--emerald-accent);
  background: rgba(5, 150, 105, 0.1);
  padding: 4px 12px;
  border-radius: var(--radius-full);
}

/* 8 Platforms Matrix Grid */
.platforms-8-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
}

.platform-pill-card {
  background: #ffffff;
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
  transition: var(--transition-snappy);
}

.platform-pill-card svg {
  color: var(--emerald-accent);
  flex-shrink: 0;
}

.platform-pill-card:hover,
.platform-pill-card.selected {
  background: rgba(5, 150, 105, 0.1);
  border-color: var(--emerald-accent);
  color: #065f46;
  box-shadow: 0 4px 15px rgba(5, 150, 105, 0.15);
  transform: translateY(-2px);
}

/* 6 Smart City Sectors Grid */
.sectors-6-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 14px;
}

.sector-tile {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 18px 14px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
  transition: var(--transition-snappy);
}

.sector-tile:hover {
  background: rgba(2, 132, 199, 0.08);
  border-color: var(--cyan-bright);
  transform: translateY(-3px);
}

.sector-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(2, 132, 199, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--cyan-bright);
}

.sector-tile:nth-child(2) .sector-icon {
  background: rgba(5, 150, 105, 0.1);
  color: var(--emerald-accent);
}

.sector-tile:nth-child(3) .sector-icon {
  background: rgba(37, 99, 235, 0.1);
  color: var(--blue-brand);
}

.sector-tile:nth-child(4) .sector-icon {
  background: rgba(217, 119, 6, 0.1);
  color: var(--amber-accent);
}

.sector-tile:nth-child(5) .sector-icon {
  background: rgba(124, 58, 237, 0.1);
  color: var(--purple-accent);
}

.sector-tile:nth-child(6) .sector-icon {
  background: rgba(5, 150, 105, 0.1);
  color: var(--emerald-accent);
}

.sector-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.3;
}

/* Four Pillars of Data Security & Quality */
.quality-security-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 10px;
}

.pillar-box {
  background: #ffffff;
  border-left: 3px solid var(--emerald-accent);
  border-top: 1px solid var(--border-subtle);
  border-right: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 18px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

.pillar-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.pillar-title svg {
  color: var(--emerald-accent);
}

.pillar-desc {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ==========================================================================
   INFOGRAPHIC 3: NĂNG LỰC PHÁT TRIỂN MỚI (LIGHT)
   ========================================================================== */
.infographic-card.theme-amber {
  border-color: rgba(217, 119, 6, 0.35);
  box-shadow: 0 12px 28px -6px rgba(217, 119, 6, 0.12), var(--shadow-ambient);
}

.infographic-badge.badge-amber {
  background: rgba(217, 119, 6, 0.08);
  border-color: rgba(217, 119, 6, 0.25);
  color: var(--amber-accent);
}

/* Talent Comparative Bar Visualization */
.talent-comparison-card {
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 26px;
  margin-bottom: 30px;
}

.talent-header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 24px;
}

.talent-card-title {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
}

.talent-card-title svg {
  color: var(--amber-accent);
}

.talent-bars-group {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.talent-bar-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.talent-bar-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-secondary);
}

.talent-bar-meta .stat-val {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  color: var(--text-main);
}

.talent-bar-meta .stat-val.accent-amber {
  color: var(--amber-accent);
}

.talent-bar-meta .stat-val.accent-cyan {
  color: var(--cyan-bright);
}

.talent-track {
  width: 100%;
  height: 12px;
  background: rgba(15, 23, 42, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.talent-fill {
  height: 100%;
  border-radius: var(--radius-full);
  transition: width 1s cubic-bezier(0.16, 1, 0.3, 1);
}

.fill-current {
  background: #94a3b8;
}

.fill-need {
  background: linear-gradient(90deg, #f59e0b, #dc2626);
}

.fill-hanoi {
  background: linear-gradient(90deg, #0284c7, #2563eb);
}

/* Quad Innovation Model (4 Trụ Cột Hợp Tác) */
.quad-model-container {
  margin-top: 30px;
}

.quad-section-title {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
}

.quad-section-title svg {
  color: var(--amber-accent);
}

.quad-grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
  margin-bottom: 30px;
}

.quad-pillar-card {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  position: relative;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
  transition: var(--transition-smooth);
}

.quad-pillar-card:hover {
  border-color: var(--amber-accent);
  transform: translateY(-4px);
  box-shadow: 0 10px 25px rgba(217, 119, 6, 0.12);
}

.quad-role-tag {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--amber-accent);
  text-transform: uppercase;
}

.quad-title {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  color: var(--text-main);
}

.quad-desc {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* Regional Value Chain & Global Vision Dual Panel */
.regional-vision-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.vision-box-highlight {
  background: linear-gradient(135deg, rgba(217, 119, 6, 0.08) 0%, #ffffff 100%);
  border: 1px solid rgba(217, 119, 6, 0.3);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

.vision-big-number {
  font-family: var(--font-display);
  font-size: clamp(38px, 4vw, 54px);
  font-weight: 900;
  color: var(--amber-accent);
  line-height: 1;
  margin-bottom: 8px;
}

.vision-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 6px;
}

.vision-desc {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.55;
}

.regional-chain-box {
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
}

.regional-nodes-diagram {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  margin: 16px 0;
}

.region-node {
  background: #ffffff;
  border: 1px solid var(--border-medium);
  padding: 8px 14px;
  border-radius: var(--radius-full);
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

.region-node.hub-node {
  background: rgba(2, 132, 199, 0.1);
  border-color: var(--cyan-bright);
  color: var(--cyan-bright);
}

.region-connector-arrow {
  color: var(--amber-accent);
  font-size: 20px;
  font-weight: bold;
}

.rd-locations-list {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.6;
  border-top: 1px solid var(--border-subtle);
  padding-top: 12px;
}

.rd-locations-list strong {
  color: var(--text-main);
}

/* ==========================================================================
   ARTICLE FOOTER & SIGNATURE
   ========================================================================== */
.article-signoff {
  max-width: var(--content-max-width);
  margin: 40px auto 80px;
  padding: 0 24px;
  display: flex;
  justify-content: flex-end;
}

.author-badge-card {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  background: #ffffff;
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-full);
  padding: 10px 24px;
  box-shadow: var(--shadow-card);
}

.author-avatar-circle {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--cyan-bright), var(--blue-brand));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-weight: 800;
  font-size: 18px;
}

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

.author-label {
  font-size: 16px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.author-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-main);
}

/* Back to Top Floating Button */
.back-to-top-btn {
  position: fixed;
  bottom: 24px;
  left: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-glass-heavy);
  border: 1px solid var(--border-medium);
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 900;
  opacity: 0;
  visibility: hidden;
  box-shadow: var(--shadow-card);
  transition: var(--transition-smooth);
}

.back-to-top-btn.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top-btn:hover {
  background: var(--cyan-bright);
  color: #ffffff;
  border-color: var(--cyan-bright);
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(2, 132, 199, 0.3);
}

/* ==========================================================================
   SCROLL REVEAL ANIMATIONS
   ========================================================================== */
.reveal-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

.reveal-on-scroll.is-revealed {
  opacity: 1;
  transform: translateY(0);
}

/* Delay modifiers */
.delay-100 {
  transition-delay: 0.1s;
}

.delay-200 {
  transition-delay: 0.2s;
}

.delay-300 {
  transition-delay: 0.3s;
}

/* ==========================================================================
   RESPONSIVE DESIGN (DESKTOP, TABLET, MOBILE)
   ========================================================================== */
@media (max-width: 992px) {

  .dual-infographic-columns,
  .regional-vision-row {
    grid-template-columns: 1fr;
  }

  .article-title {
    font-size: 2.8rem;
  }

  .infographic-card {
    padding: 30px 24px;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 18px;
    /* Strict >= 16px */
    line-height: 1.8;
  }

  .hero-section {
    padding: 100px 16px 40px;
    min-height: 85vh;
  }

  .article-title {
    font-size: 2.2rem;
    margin-bottom: 20px;
  }

  .sapo-box {
    padding: 24px 20px;
  }

  .sapo-text {
    font-size: 19px;
  }

  .section-title {
    font-size: 2rem;
  }

  .editorial-p {
    font-size: 18px;
    text-align: left;
  }

  .has-dropcap::first-letter {
    font-size: 4rem;
    padding-right: 10px;
  }

  .infographic-wrapper,
  .photo-breakout {
    padding: 0 16px;
  }

  .infographic-card {
    padding: 24px 18px;
  }

  .metrics-grid-4,
  .platforms-8-grid,
  .quad-grid-4 {
    grid-template-columns: 1fr;
  }

  .sectors-6-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .reading-tracker {
    bottom: 16px;
    right: 16px;
    padding: 4px 10px;
  }

  .tracker-pills {
    display: none;
    /* Hide pills on small screens, keep percentage and dot */
  }

  .back-to-top-btn {
    bottom: 16px;
    left: 16px;
  }
}

@media (max-width: 480px) {
  .sectors-6-grid {
    grid-template-columns: 1fr;
  }

  .controls-timeline-bar {
    flex-direction: column;
    align-items: stretch;
  }

  .timeline-toggle-group {
    justify-content: center;
  }
}