/* ==========================================================================
   KNWLDG Systems & TunTun VPN — Light Design System
   Website: https://knwldg.info
   Theme: TuntunLight / Modern Systems Paper Palette
   ========================================================================== */

:root {
  /* Core Light Palette (from Android Theme.kt TuntunLight & colors.xml) */
  --bg-primary: #F6FBF5;
  --bg-secondary: #EEF4EE;
  --bg-tertiary: #E2EAE3;
  --bg-card: #FFFFFF;
  --bg-card-hover: #FFFFFF;
  --border-subtle: rgba(27, 107, 76, 0.14);
  --border-active: #1B6B4C;
  --border-cyan: rgba(2, 132, 199, 0.25);

  /* TunTun Brand Colors */
  --tt-green-seed: #1B6B4C;
  --tt-green-primary: #1B6B4C;
  --tt-green-bright: #108658;
  --tt-green-container: #E4F6ED;
  --tt-green-on-container: #003825;
  --tt-bg-launch: #F6FBF5;

  /* Accents */
  --accent-cyan: #0284C7;
  --accent-blue: #2563EB;
  --accent-purple: #7C3AED;
  --accent-amber: #D97706;
  --accent-red: #DC2626;

  /* High-Contrast Crisp Typography Colors */
  --text-primary: #171D19;
  --text-secondary: #404942;
  --text-tertiary: #6B776E;
  --text-inverse: #FFFFFF;

  /* Fonts */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', 'Plus Jakarta Sans', system-ui, sans-serif;
  --font-mono: ui-monospace, 'SF Mono', 'JetBrains Mono', 'Fira Code', Menlo, Monaco, Consolas, monospace;

  /* Layout */
  --max-width: 1240px;
  --header-height: 72px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 9999px;

  /* Shadows & Glows (Refined for Light Theme) */
  --glow-emerald: 0 4px 24px rgba(27, 107, 76, 0.12);
  --glow-cyan: 0 4px 24px rgba(2, 132, 199, 0.12);
  --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.04), 0 1px 3px rgba(27, 107, 76, 0.06);
  --shadow-card-hover: 0 12px 32px rgba(27, 107, 76, 0.12), 0 2px 6px rgba(0, 0, 0, 0.04);
  --transition-fast: 0.18s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-color: var(--bg-primary);
  -webkit-overflow-scrolling: touch;
}

/* Background Network Mesh / Subtle Canvas */
#bg-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  pointer-events: none;
  opacity: 0.35;
  transform: translateZ(0);
  will-change: transform;
}

/* Vignette Gradient */
.bg-vignette {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 50% 15%, transparent 20%, var(--bg-primary) 90%);
  pointer-events: none;
  z-index: -1;
  transform: translateZ(0);
  will-change: transform;
}

/* Container */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Typography Utilities */
h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h1 {
  font-size: clamp(2.4rem, 5vw, 4.2rem);
  font-weight: 800;
  letter-spacing: -0.035em;
}

h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  letter-spacing: -0.025em;
  margin-bottom: 16px;
}

h3 {
  font-size: 1.35rem;
  margin-bottom: 8px;
}

p {
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.7;
}

code, pre, .mono {
  font-family: var(--font-mono);
}

.gradient-text {
  background: linear-gradient(135deg, #171D19 20%, #1B6B4C 80%, #0284C7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gradient-text-emerald {
  background: linear-gradient(135deg, #1B6B4C 0%, #108658 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Buttons & Badges */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #1B6B4C 0%, #108658 100%);
  color: #FFFFFF;
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(27, 107, 76, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(27, 107, 76, 0.35);
  background: linear-gradient(135deg, #14553B 0%, #0E754C 100%);
}

.btn-secondary {
  background: #FFFFFF;
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
}

.btn-secondary:hover {
  background: #F0F5EF;
  border-color: rgba(27, 107, 76, 0.3);
  transform: translateY(-2px);
}

.btn-glow-cyan {
  background: rgba(2, 132, 199, 0.08);
  color: #0284C7;
  border: 1px solid rgba(2, 132, 199, 0.3);
}

.btn-glow-cyan:hover {
  background: rgba(2, 132, 199, 0.15);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 0.85rem;
  border-radius: var(--radius-sm);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-family: var(--font-mono);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(27, 107, 76, 0.08);
  color: #1B6B4C;
  border: 1px solid rgba(27, 107, 76, 0.22);
}

.badge-cyan {
  background: rgba(2, 132, 199, 0.08);
  color: #0284C7;
  border-color: rgba(2, 132, 199, 0.24);
}

.badge-amber {
  background: rgba(217, 119, 6, 0.08);
  color: #B45309;
  border-color: rgba(217, 119, 6, 0.24);
}

.badge-pulse::before {
  content: '';
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: currentColor;
  box-shadow: 0 0 8px currentColor;
  animation: pulseDot 2s infinite ease-in-out;
}

@keyframes pulseDot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.7); }
}

/* Header & Nav */
.header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: rgba(246, 251, 245, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  z-index: 100;
  transform: translateZ(0);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
}

.brand-logo {
  width: 36px;
  height: 36px;
}

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

.brand-name {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  font-family: var(--font-mono);
  color: #171D19;
}

.brand-sub {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: #1B6B4C;
  font-weight: 700;
}

.nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 600;
  transition: color var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
  color: #1B6B4C;
}

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

.mobile-menu-btn {
  display: none;
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
}

/* Hero Section */
.hero {
  padding: 80px 0 60px;
  position: relative;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.hero-pill-box {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.hero-title {
  max-width: 680px;
}

.hero-desc {
  max-width: 600px;
  font-size: 1.15rem;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 10px;
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.88rem;
  color: var(--text-tertiary);
  font-family: var(--font-mono);
}

.hero-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}

/* Hero Overview Console */
.hero-visual {
  position: relative;
}

.hero-overview-console {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: relative;
  overflow: hidden;
}

.hero-overview-console::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #1B6B4C, #0284C7, #2563EB);
}

.console-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 14px;
}

.console-title {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  color: #171D19;
  letter-spacing: 0.05em;
}

.console-disciplines-flow {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 10px;
  margin: 10px 0;
}

.flow-node {
  background: #F6FBF5;
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 12px 6px;
  text-align: center;
  transition: all var(--transition-fast);
  text-decoration: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.flow-node:hover {
  border-color: #1B6B4C;
  background: #EAF5EF;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(27, 107, 76, 0.1);
}

.flow-letter {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 800;
  color: #171D19;
}

.flow-label {
  font-size: 0.68rem;
  text-transform: uppercase;
  color: var(--text-tertiary);
  letter-spacing: 0.04em;
  font-weight: 600;
}

.console-summary-box {
  background: #F0F5EF;
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 14px;
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Sections General */
.section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 820px;
  margin: 0 auto 56px;
}

.section-tag {
  display: inline-block;
  margin-bottom: 14px;
}

.section-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   CORE OFFERINGS / DISCIPLINES GRID
   ========================================================================== */
.disciplines-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr));
  gap: 24px;
}

.discipline-card {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-card);
}

.discipline-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.discipline-card:hover {
  transform: translateY(-4px);
  border-color: rgba(27, 107, 76, 0.4);
  box-shadow: var(--shadow-card-hover);
}

.discipline-card:hover::before {
  opacity: 1;
}

.discipline-card[data-discipline="K"]::before { background: #1B6B4C; }
.discipline-card[data-discipline="N"]::before { background: #0284C7; }
.discipline-card[data-discipline="W"]::before { background: #2563EB; }
.discipline-card[data-discipline="L"]::before { background: #D97706; }
.discipline-card[data-discipline="D"]::before { background: #7C3AED; }
.discipline-card[data-discipline="G"]::before { background: #108658; }

.discipline-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
}

.discipline-letter-box {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 1.7rem;
  font-weight: 800;
}

.discipline-card[data-discipline="K"] .discipline-letter-box { background: rgba(27, 107, 76, 0.1); border: 1px solid rgba(27, 107, 76, 0.25); color: #1B6B4C; }
.discipline-card[data-discipline="N"] .discipline-letter-box { background: rgba(2, 132, 199, 0.1); border: 1px solid rgba(2, 132, 199, 0.25); color: #0284C7; }
.discipline-card[data-discipline="W"] .discipline-letter-box { background: rgba(37, 99, 235, 0.1); border: 1px solid rgba(37, 99, 235, 0.25); color: #2563EB; }
.discipline-card[data-discipline="L"] .discipline-letter-box { background: rgba(217, 119, 6, 0.1); border: 1px solid rgba(217, 119, 6, 0.25); color: #B45309; }
.discipline-card[data-discipline="D"] .discipline-letter-box { background: rgba(124, 58, 237, 0.1); border: 1px solid rgba(124, 58, 237, 0.25); color: #7C3AED; }
.discipline-card[data-discipline="G"] .discipline-letter-box { background: rgba(16, 134, 88, 0.1); border: 1px solid rgba(16, 134, 88, 0.25); color: #108658; }

.discipline-scope {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-tertiary);
  text-transform: uppercase;
  font-weight: 600;
}

.discipline-name {
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: #171D19;
}

.discipline-definition {
  font-size: 0.98rem;
  line-height: 1.65;
  color: var(--text-secondary);
  margin-bottom: 20px;
  flex-grow: 1;
}

.discipline-primitives {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
}

.primitive-tag {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  background: #F0F5EF;
  padding: 5px 10px;
  border-radius: 4px;
  color: #404942;
  border: 1px solid rgba(27, 107, 76, 0.12);
  font-weight: 500;
}

/* ==========================================================================
   SPOTLIGHT TEASER: TUNTUN VPN (LIGHT THEME)
   ========================================================================== */
.tuntun-teaser-section {
  padding: 80px 0;
  position: relative;
}

.tuntun-teaser-card {
  background: radial-gradient(circle at 85% 20%, rgba(27, 107, 76, 0.08) 0%, transparent 60%),
              radial-gradient(circle at 15% 80%, rgba(2, 132, 199, 0.06) 0%, transparent 60%),
              #FFFFFF;
  border: 1px solid rgba(27, 107, 76, 0.22);
  border-radius: var(--radius-lg);
  padding: 48px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 10px 40px rgba(27, 107, 76, 0.08);
  transition: all var(--transition-smooth);
}

.tuntun-teaser-card:hover {
  border-color: rgba(27, 107, 76, 0.4);
  transform: translateY(-2px);
  box-shadow: 0 16px 48px rgba(27, 107, 76, 0.14);
}

.tuntun-teaser-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: center;
}

.tuntun-teaser-info {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.tuntun-teaser-badge-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.tuntun-teaser-header {
  display: flex;
  align-items: center;
  gap: 18px;
}

.tuntun-teaser-logo {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  box-shadow: 0 6px 18px rgba(27, 107, 76, 0.25);
}

.tuntun-teaser-title {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #171D19;
}

.tuntun-teaser-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.tuntun-teaser-highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
  margin: 8px 0;
}

.teaser-highlight-item {
  background: #F6FBF5;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.teaser-highlight-icon {
  font-size: 1.1rem;
  line-height: 1.2;
}

.teaser-highlight-text {
  font-size: 0.88rem;
  color: var(--text-primary);
  font-weight: 500;
  line-height: 1.4;
}

.tuntun-teaser-action-row {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 8px;
  flex-wrap: wrap;
}

/* Teaser Right Visual */
.tuntun-teaser-visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
}

.teaser-device-preview {
  background: #FFFFFF;
  border: 3px solid #CEE9DA;
  border-radius: 28px;
  padding: 24px;
  width: 100%;
  max-width: 320px;
  box-shadow: 0 16px 40px rgba(27, 107, 76, 0.12);
  text-align: center;
}

.preview-state-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #1B6B4C;
  box-shadow: 0 0 8px #1B6B4C;
  display: inline-block;
  margin-right: 6px;
}

/* Philosophy Section */
.philosophy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.philosophy-card {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: all var(--transition-smooth);
  box-shadow: var(--shadow-card);
}

.philosophy-card:hover {
  border-color: rgba(27, 107, 76, 0.35);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card-hover);
}

.philosophy-num {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  color: #1B6B4C;
}

.philosophy-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: #171D19;
}

.philosophy-text {
  font-size: 0.98rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* Roadmap Grid */
.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.roadmap-card {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-card);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
}

.roadmap-card:hover {
  border-color: rgba(27, 107, 76, 0.35);
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.roadmap-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.roadmap-card-header h4 {
  font-size: 1.12rem;
  font-weight: 700;
  color: #171D19;
  line-height: 1.35;
  margin: 0;
}

.roadmap-status {
  position: static;
  flex-shrink: 0;
  white-space: nowrap;
  font-size: 0.72rem;
  padding: 3px 10px;
  line-height: 1.3;
}

.roadmap-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.55;
  flex-grow: 1;
}

/* ==========================================================================
   TUNTUN VPN SIMULATOR & COMPONENT POLISH (LIGHT THEME)
   ========================================================================== */
.phone-mockup-wrapper {
  position: relative;
  display: flex;
  justify-content: center;
}

.phone-mockup {
  width: 100%;
  max-width: 340px;
  height: 680px;
  background: #F6FBF5; /* TuntunLight background */
  border-radius: 44px;
  border: 10px solid #DFE7E0;
  box-sizing: border-box;
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.12), 0 0 35px rgba(27, 107, 76, 0.15);
  position: relative;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  user-select: none;
}

.phone-notch {
  width: 120px;
  height: 18px;
  background: #DFE7E0;
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  border-bottom-left-radius: 12px;
  border-bottom-right-radius: 12px;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
}

.camera-lens {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #171D19;
}

.sim-app-header {
  padding: 26px 20px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-subtle);
  background: #FFFFFF;
}

.sim-app-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.sim-logo-tiny {
  width: 26px;
  height: 26px;
  border-radius: 6px;
}

.sim-app-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #171D19;
}

.sim-config-btn {
  background: none;
  border: none;
  color: #1B6B4C;
  font-size: 0.78rem;
  font-weight: 700;
  cursor: pointer;
}

.sim-screen-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
  justify-content: space-between;
}

.sim-hero-box {
  background: #FFFFFF;
  border-radius: 18px;
  padding: 20px;
  text-align: center;
  border: 1px solid #DFE7E0;
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.sim-hero-box.connected {
  background: #E4F6ED;
  border-color: #A4F2C9;
}

.sim-hero-box.connecting {
  background: #C0E9FB;
  border-color: #7DD3FC;
}

.sim-state-badge {
  display: inline-block;
  font-size: 0.75rem;
  text-transform: uppercase;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #707972;
  margin-bottom: 4px;
}

.sim-state-text {
  font-size: 1.5rem;
  font-weight: 800;
  color: #171D19;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.sim-state-text.connected {
  color: #1B6B4C;
}

.sim-state-sub {
  font-size: 0.8rem;
  color: #707972;
  font-family: var(--font-mono);
}

.sim-action-btn {
  width: 100%;
  padding: 16px;
  border-radius: 14px;
  font-size: 1.05rem;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  background: #1B6B4C;
  color: #FFFFFF;
  margin: 12px 0;
  box-shadow: 0 4px 16px rgba(27, 107, 76, 0.3);
}

.sim-action-btn:hover {
  background: #14553B;
  transform: scale(1.02);
}

.sim-action-btn.btn-disconnect {
  background: #CEE9DA;
  color: #003825;
  box-shadow: none;
}

.sim-counters-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #707972;
  margin-bottom: 8px;
  font-family: var(--font-mono);
}

.sim-counters-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.sim-counter-card {
  background: #FFFFFF;
  border: 1px solid #DFE7E0;
  border-radius: 10px;
  padding: 8px 12px;
}

.sim-counter-label {
  font-size: 0.68rem;
  color: #707972;
  text-transform: uppercase;
  margin-bottom: 2px;
}

.sim-counter-val {
  font-size: 0.95rem;
  font-weight: 700;
  color: #171D19;
  font-family: var(--font-mono);
}

.pulse-ring {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #1B6B4C;
  box-shadow: 0 0 8px #1B6B4C;
  animation: pulseDot 1.6s infinite;
}

.sim-connecting-spinner {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid rgba(27, 107, 76, 0.2);
  border-top-color: #1B6B4C;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.sim-toast {
  position: absolute;
  top: 60px;
  left: 20px;
  right: 20px;
  background: #171D19;
  border: 1px solid #1B6B4C;
  color: #FFFFFF;
  font-size: 0.74rem;
  line-height: 1.4;
  padding: 10px 12px;
  border-radius: 8px;
  z-index: 20;
  box-shadow: 0 4px 18px rgba(0, 0, 0, 0.2);
  opacity: 0;
  pointer-events: none;
  transform: translateY(-8px);
  transition: all 0.25s ease;
  font-family: var(--font-mono);
}

.sim-toast.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.sim-config-modal {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: #FFFFFF;
  z-index: 30;
  display: flex;
  flex-direction: column;
  padding: 24px 20px;
  transform: translateY(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
}

.sim-config-modal.active {
  transform: translateY(0);
}

.sim-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid #DFE7E0;
}

.sim-modal-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #171D19;
}

.sim-close-btn {
  background: #EEF4EE;
  border: 1px solid #DFE7E0;
  color: #171D19;
  font-size: 0.8rem;
  padding: 4px 10px;
  border-radius: 6px;
  cursor: pointer;
}

.sim-config-code {
  background: #F6FBF5;
  border: 1px solid #DFE7E0;
  border-radius: 8px;
  padding: 14px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.55;
  color: #1B6B4C;
  white-space: pre-wrap;
  word-break: break-all;
}

.sim-roaming-hint {
  font-size: 0.7rem;
  color: #707972;
  background: #FFFFFF;
  border: 1px solid #DFE7E0;
  border-radius: 6px;
  padding: 8px 10px;
  margin-top: 10px;
  line-height: 1.4;
  border-left: 3px solid #1B6B4C;
}

/* Architecture Card in tuntun.html */
.arch-card {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-card);
}

.arch-img-wrapper {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border-radius: var(--radius-md);
  margin-bottom: 24px;
  border: 1px solid var(--border-subtle);
  background: #FFFFFF;
}

.arch-img-wrapper img {
  width: 100%;
  height: auto;
  display: block;
}

.mobile-scroll-hint {
  display: none;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #1B6B4C;
  font-weight: 600;
  text-align: center;
  margin-bottom: 12px;
  background: rgba(27, 107, 76, 0.06);
  border: 1px dashed rgba(27, 107, 76, 0.25);
  border-radius: 6px;
  padding: 6px 12px;
}

.tuntun-metrics-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 20px;
}

/* Footer (Light Theme) */
.footer {
  background: #EEF4EE;
  border-top: 1px solid var(--border-subtle);
  padding: 80px 0 40px;
  color: var(--text-secondary);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 60px;
}

.footer-brand-col {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.footer-col h5 {
  color: #171D19;
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 20px;
  font-family: var(--font-mono);
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.92rem;
  transition: color var(--transition-fast);
}

.footer-col a:hover {
  color: #1B6B4C;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 32px;
  border-top: 1px solid rgba(27, 107, 76, 0.1);
  font-size: 0.85rem;
  color: var(--text-tertiary);
}

/* ==========================================================================
   RESPONSIVE MEDIA QUERIES (COMPREHENSIVE MOBILE OPTIMIZATION)
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 992px) {
  .tuntun-teaser-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .tuntun-product-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .console-disciplines-flow {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  /* Disable heavy background canvas animation on mobile for 60fps smooth scrolling */
  #bg-canvas {
    display: none !important;
  }

  /* Header & Navigation Drawer */
  .header-actions .btn {
    display: none;
  }

  .nav {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(246, 251, 245, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 24px;
    gap: 18px;
    border-bottom: 1px solid var(--border-subtle);
    box-shadow: 0 16px 36px rgba(0, 0, 0, 0.08);
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity var(--transition-fast), transform var(--transition-fast);
  }

  .nav.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav-link {
    font-size: 1.05rem;
    padding: 6px 0;
  }

  .mobile-menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  /* Spacing & Layout */
  .hero {
    padding: 48px 0 24px;
  }

  .section {
    padding: 60px 0;
  }

  .hero-overview-console {
    padding: 20px 16px;
  }

  .hero-meta {
    flex-wrap: wrap;
    gap: 10px 18px;
  }

  .disciplines-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

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

  .tuntun-teaser-card {
    padding: 28px 18px;
  }

  .philosophy-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

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

  .roadmap-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .roadmap-card {
    padding: 22px 18px;
  }

  .feature-cards-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .arch-card {
    padding: 20px 14px;
  }

  .arch-img-wrapper img {
    min-width: 680px;
  }

  .mobile-scroll-hint {
    display: block;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}

@media (max-width: 520px) {
  .tuntun-metrics-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  h1 {
    font-size: 2.1rem;
    line-height: 1.2;
    overflow-wrap: break-word;
    word-break: break-word;
  }

  h2 {
    font-size: 1.65rem;
    line-height: 1.25;
  }

  .hero-cta {
    flex-direction: column;
  }

  .hero-cta .btn {
    width: 100%;
    justify-content: center;
  }

  .tuntun-teaser-action-row {
    flex-direction: column;
    align-items: stretch;
  }

  .tuntun-teaser-action-row .btn {
    width: 100%;
    justify-content: center;
  }

  .console-disciplines-flow {
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
  }

  .flow-node {
    padding: 10px 4px;
  }

  .flow-letter {
    font-size: 1.2rem;
  }

  .flow-label {
    font-size: 0.62rem;
  }

  .tuntun-teaser-card {
    padding: 20px 14px;
  }

  .teaser-device-preview {
    max-width: 100%;
    padding: 18px 12px;
  }

  .phone-mockup {
    max-width: 310px;
    height: 600px;
    border-width: 6px;
    border-radius: 34px;
  }

  .phone-notch {
    width: 96px;
    height: 14px;
  }

  .sim-screen-body {
    padding: 14px 12px;
    gap: 12px;
  }

  .sim-action-btn {
    padding: 13px 18px;
    font-size: 0.98rem;
  }

  .platform-install-card {
    padding: 20px 16px;
  }

  .brand-name {
    font-size: 1.15rem;
  }
}

@media (max-width: 360px) {
  .tuntun-metrics-grid {
    grid-template-columns: 1fr;
  }
}