@import url('https://fonts.googleapis.com/css2?family=Courier+Prime:ital,wght@0,400;0,700;1,400&family=Outfit:wght@300;400;500;600;700&family=Playfair+Display:ital,wght@0,400;0,600;0,700;1,400&display=swap');

/* ==========================================================================
   Binary 16 Labs // Canonical Design System
   Theme: Institutional Modernism & Editorial Symmetry
   Architecture: Responsive Scroll Journey & Floating Glass HUD
   ========================================================================== */

:root {
  /* Institutional Alabaster & Cream (Editorial Reading Zones) */
  --bg-alabaster: #F5F2EB;
  --bg-cream-card: #EAE5D9;
  --bg-cream-hover: #DFDAD0;
  
  /* Deep Moss Green Sanctuary (Technical & 3D Substrates) */
  --bg-moss: #1E2D24;
  --bg-moss-dark: #16221B;
  --bg-moss-surface: #26382D;
  
  /* Earthy Retro Accents */
  --accent-rust: #B85D3D;
  --accent-rust-hover: #A04E31;
  --accent-sage: #9CAF88;
  --accent-sage-light: #B4C4A3;
  --border-taupe: #C5B38E;
  
  /* Typography Colors */
  --text-charcoal: #1A241E;
  --text-alabaster: #F5F2EB;
  --text-muted-dark: rgba(26, 36, 30, 0.68);
  --text-muted-light: rgba(245, 242, 235, 0.68);
  
  /* Typography Families */
  --font-serif: 'Playfair Display', Georgia, serif;
  --font-sans: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'Courier Prime', 'Courier New', monospace;
  
  /* Layout & Animation */
  --transition-smooth: all 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
}

/* ==========================================================================
   Global Reset & Neuro-Assist Override Foundations
   ========================================================================== */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-alabaster);
  color: var(--text-charcoal);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
  transition: var(--transition-smooth);
}

/* Dyslexic font override */
body.neuro-dyslexic * {
  font-family: 'Lexend', var(--font-sans), sans-serif !important;
  letter-spacing: 0.03em;
}

/* Line spacing override */
body.neuro-spacing {
  line-height: 1.95 !important;
}

body.neuro-spacing p, 
body.neuro-spacing li {
  margin-bottom: 1.2rem !important;
}

/* Bionic reading anchors */
.bionic-anchor {
  font-weight: 700 !important;
  color: var(--accent-rust);
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   Navigation // Symmetrical Boxed Navbar
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(245, 242, 235, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 2px solid var(--border-taupe);
  padding: 14px 0;
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text-charcoal);
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: 0.02em;
  flex-shrink: 0;
  white-space: nowrap;
}

.brand-logo {
  height: 24px;
  width: auto;
  max-width: 28px;
  object-fit: contain;
  border: none;
  border-radius: 0;
  flex-shrink: 0;
}

.brand-icon {
  width: 34px;
  height: 34px;
  background: var(--bg-moss);
  color: var(--bg-alabaster);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1rem;
  border: 1.5px solid var(--border-taupe);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--accent-rust);
  border: 1px solid var(--accent-rust);
  padding: 2px 8px;
  border-radius: 100px;
  text-transform: uppercase;
  white-space: nowrap;
  flex-shrink: 0;
}

@media (max-width: 1250px) {
  .brand-tag {
    display: none;
  }
}

@media (max-width: 1024px) {
  .nav-links {
    display: none;
  }
}

.nav-links {
  display: flex;
  gap: 16px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-charcoal);
  font-weight: 500;
  font-size: 0.88rem;
  padding: 4px 6px;
  border-bottom: 2px solid transparent;
  transition: var(--transition-smooth);
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent-rust);
  border-bottom-color: var(--accent-rust);
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* ==========================================================================
   Buttons & Interactive Elements (Retro Modernism)
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.88rem;
  text-decoration: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition-smooth);
  border: 1.5px solid transparent;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.btn-primary {
  background: var(--accent-rust);
  color: var(--bg-alabaster);
  border-color: var(--accent-rust);
  box-shadow: 0 4px 12px rgba(184, 93, 61, 0.25);
}

.btn-primary:hover {
  background: var(--accent-rust-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(184, 93, 61, 0.35);
}

.btn-secondary {
  background: transparent;
  color: var(--bg-moss);
  border-color: var(--bg-moss);
}

.btn-secondary:hover {
  background: var(--bg-moss);
  color: var(--bg-alabaster);
}

.btn-audio {
  background: var(--bg-cream-card);
  color: var(--text-charcoal);
  border: 1.5px solid var(--border-taupe);
  font-family: var(--font-mono);
  font-size: 0.78rem;
}

.btn-audio.playing {
  background: var(--accent-sage);
  color: var(--bg-moss-dark);
  border-color: var(--bg-moss);
  font-weight: 700;
}

/* ==========================================================================
   Section 1: Hero Studio // Institutional Symmetry
   ========================================================================== */
.hero {
  padding: 70px 0 60px;
  text-align: center;
  border-bottom: 2px solid var(--border-taupe);
  background: radial-gradient(circle at 50% 20%, rgba(197, 179, 142, 0.18) 0%, transparent 70%);
}

.hero-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--accent-rust);
  background: var(--bg-cream-card);
  border: 1.5px solid var(--border-taupe);
  padding: 6px 16px;
  border-radius: var(--radius-sm);
  margin-bottom: 22px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: 3.4rem;
  font-weight: 700;
  line-height: 1.15;
  color: var(--text-charcoal);
  max-width: 900px;
  margin: 0 auto 22px;
}

.hero-title span {
  color: var(--accent-rust);
  font-style: italic;
  font-weight: 600;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted-dark);
  max-width: 760px;
  margin: 0 auto 38px;
  font-weight: 400;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 18px;
  margin-bottom: 54px;
}

/* ==========================================================================
   Architecture Showcase Helper Styling
   ========================================================================== */
.chapter-specs {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.chapter-specs li {
  font-size: 0.92rem;
  color: var(--text-charcoal);
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.chapter-specs li::before {
  content: "➔";
  color: var(--accent-rust);
  font-weight: 700;
}

/* ==========================================================================
   CINEMATIC ACTS // Mobile-First Floating Glass HUD over Sticky Substrates
   ========================================================================== */
.cinematic-act {
  position: relative;
  background: var(--bg-moss-dark);
  color: var(--text-alabaster);
  border-bottom: 2px solid var(--border-taupe);
}

/* Sticky Background Substrate Container */
.sticky-substrate {
  position: sticky;
  top: 72px;
  height: calc(100vh - 74px);
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1;
  overflow: hidden;
  pointer-events: none; /* Let clicks/scroll pass through to floating cards */
}

/* Act I Substrate: Fullscreen 3D Canvas */
.blueprint-canvas-container {
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, var(--bg-moss) 0%, var(--bg-moss-dark) 100%);
  position: relative;
}

#blueprintCanvas {
  width: 100%;
  height: 100%;
  display: block;
}

.substrate-badge {
  position: absolute;
  top: 20px; left: 24px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-sage);
  background: rgba(22, 34, 27, 0.88);
  padding: 6px 14px;
  border: 1px solid var(--accent-sage);
  border-radius: var(--radius-sm);
  pointer-events: none;
  z-index: 5;
}

.substrate-status {
  position: absolute;
  bottom: 20px; right: 24px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--border-taupe);
  background: rgba(22, 34, 27, 0.88);
  padding: 6px 14px;
  border: 1px solid var(--border-taupe);
  border-radius: var(--radius-sm);
  pointer-events: none;
  z-index: 5;
}

/* Act II Substrate: Cockpit Telemetry HUD */
.cockpit-hud-container {
  width: 90%;
  max-width: 1040px;
  height: 78%;
  background: rgba(22, 34, 27, 0.94);
  border: 2px solid var(--border-taupe);
  border-radius: var(--radius-md);
  padding: 32px;
  box-shadow: 0 24px 60px rgba(0,0,0,0.6);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hud-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px dashed rgba(197, 179, 142, 0.4);
  padding-bottom: 12px;
  margin-bottom: 20px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-sage);
}

.hud-screen {
  background: rgba(0,0,0,0.4);
  border: 1px solid rgba(197, 179, 142, 0.3);
  border-radius: var(--radius-sm);
  padding: 24px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.65;
  color: var(--bg-alabaster);
  white-space: pre-wrap;
  overflow-x: auto;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* Act II/III Substrates: Institutional Architecture Graph & CLI Console */
.textual-tui-container, .arch-graph-container {
  width: 92%;
  max-width: 1120px;
  height: 82%;
  background: rgba(14, 20, 16, 0.98);
  border: 2px solid var(--border-taupe);
  border-radius: var(--radius-md);
  box-shadow: 0 24px 64px rgba(0,0,0,0.7);
  display: flex;
  flex-direction: column;
  font-family: var(--font-mono);
  overflow: hidden;
  color: var(--bg-alabaster);
}

.arch-graph-canvas-wrap {
  flex: 1;
  position: relative;
  background: radial-gradient(circle at 50% 50%, rgba(30, 45, 36, 0.6) 0%, rgba(14, 20, 16, 0.98) 100%);
  overflow: hidden;
  display: flex;
}

canvas#archGraphCanvas {
  width: 100%;
  height: 100%;
  display: block;
}

.arch-graph-overlay {
  position: absolute;
  bottom: 20px;
  right: 20px;
  left: 20px;
  background: rgba(22, 34, 27, 0.9);
  border: 1.5px solid var(--border-taupe);
  border-radius: var(--radius-sm);
  padding: 14px 18px;
  backdrop-filter: blur(8px);
  pointer-events: none;
  transition: all 0.3s ease;
  box-shadow: 0 8px 24px rgba(0,0,0,0.5);
}

.overlay-title {
  color: var(--accent-rust);
  font-weight: 700;
  font-size: 0.85rem;
  margin-bottom: 4px;
  letter-spacing: 0.05em;
}

.overlay-stats {
  color: var(--accent-sage-light);
  font-size: 0.78rem;
  font-weight: 700;
  margin-bottom: 6px;
  font-family: var(--font-mono);
}

.overlay-desc {
  color: var(--text-alabaster);
  font-size: 0.85rem;
  line-height: 1.4;
  font-family: var(--font-serif);
}

.tui-header {
  background: var(--bg-moss-surface);
  padding: 10px 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1.5px solid var(--border-taupe);
  font-size: 0.82rem;
  font-weight: 700;
}

.tui-header-left, .tui-header-right { display: flex; align-items: center; gap: 10px; }
.tui-box-char { color: var(--border-taupe); font-weight: 400; }
.tui-title-accent { color: var(--text-alabaster); letter-spacing: 0.05em; }
.tui-badge-ready { color: var(--accent-sage); background: rgba(156, 175, 136, 0.15); padding: 2px 10px; border-radius: 100px; font-size: 0.72rem; }

.tui-body {
  display: flex;
  flex: 1;
  overflow: hidden;
}

.tui-sidebar {
  width: 250px;
  background: rgba(22, 34, 27, 0.6);
  border-right: 1.5px solid var(--border-taupe);
  padding: 18px 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.82rem;
}

.tui-sidebar-title {
  color: var(--border-taupe);
  font-weight: 700;
  margin-bottom: 10px;
  text-align: center;
}

.tui-tab {
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  color: var(--text-muted-light);
  cursor: default;
  transition: var(--transition-smooth);
  border: 1px solid transparent;
}

.tui-tab.active-tab {
  background: var(--bg-moss);
  color: var(--accent-rust);
  border-color: var(--accent-rust);
  font-weight: 700;
  box-shadow: 0 4px 12px rgba(184, 93, 61, 0.25);
  transform: translateX(4px);
}

.tui-sidebar-footer {
  margin-top: auto;
  border-top: 1px dashed rgba(197, 179, 142, 0.3);
  padding-top: 14px;
  font-size: 0.72rem;
  line-height: 1.6;
  text-align: center;
}

.tui-console {
  flex: 1;
  padding: 24px 32px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  font-size: 0.88rem;
  line-height: 1.7;
}

.tui-welcome {
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 1px dashed rgba(197, 179, 142, 0.3);
}

.tui-output-stream {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* Rich Textual UI Widgets inside Console */
.tui-box-panel {
  background: rgba(245, 242, 235, 0.05);
  border: 1.5px solid var(--border-taupe);
  border-radius: var(--radius-sm);
  padding: 16px;
  margin: 10px 0;
  line-height: 1.6;
}

.tui-box-title { color: var(--accent-rust); font-weight: 700; margin-bottom: 6px; display: block; text-transform: uppercase; font-size: 0.82rem; }
.tui-box-desc { color: var(--text-alabaster); font-size: 0.92rem; }
.tui-specs-list { margin-top: 10px; padding-left: 14px; color: var(--accent-sage-light); font-size: 0.82rem; }
.tui-specs-list li { margin-bottom: 4px; }

.t-line { display: flex; align-items: baseline; }
.t-prompt { color: var(--accent-rust); font-weight: 700; margin-right: 10px; }
.t-cmd { color: var(--text-alabaster); font-weight: 700; font-size: 1rem; }
.t-out { color: var(--accent-sage-light); padding-left: 18px; font-size: 0.85rem; }
.t-success { color: var(--accent-sage); font-weight: 700; padding-left: 18px; }

.tui-progress-bar {
  color: var(--accent-rust);
  font-family: var(--font-mono);
  font-weight: 700;
  padding-left: 18px;
  margin: 4px 0;
}

.tui-footer {
  background: var(--bg-moss-surface);
  padding: 8px 18px;
  display: flex;
  align-items: center;
  gap: 14px;
  border-top: 1.5px solid var(--border-taupe);
  font-size: 0.76rem;
}

.tui-footer-stat { color: var(--text-muted-light); }
.tui-footer-sep { color: var(--border-taupe); }

/* Scrolling Foreground Layer (Floating Glass HUDs) */
.floating-glass-layer {
  position: relative;
  z-index: 10;
  max-width: 1140px;
  margin: 0 auto;
  padding: 15vh 24px 25vh;
  display: flex;
  flex-direction: column;
  gap: 65vh; /* Large spacing so each card gets exclusive stage time */
  pointer-events: none; /* Let empty space pass clicks */
}

/* Floating Alabaster Glass Card */
.floating-glass-panel {
  pointer-events: auto; /* Enable interaction inside the glass card */
  width: 540px;
  background: rgba(245, 242, 235, 0.88);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 2px solid var(--border-taupe);
  border-radius: var(--radius-lg);
  padding: 36px;
  color: var(--text-charcoal);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
  transition: var(--transition-smooth);
}

.floating-glass-panel.align-left { align-self: flex-start; margin-left: 20px; }
.floating-glass-panel.align-right { align-self: flex-end; margin-right: 20px; }
.floating-glass-panel.align-center { align-self: center; }

.floating-glass-panel.active-card {
  border-color: var(--accent-rust);
  background: rgba(245, 242, 235, 0.95);
  transform: translateY(-8px) scale(1.02);
  box-shadow: 0 24px 64px rgba(184, 93, 61, 0.3);
}

.chapter-number {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-rust);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 10px;
}

.chapter-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  color: var(--text-charcoal);
  margin-bottom: 14px;
  line-height: 1.25;
}

.chapter-desc {
  font-size: 1rem;
  color: var(--text-muted-dark);
  margin-bottom: 20px;
  line-height: 1.65;
}

.chapter-specs {
  list-style: none;
  border-top: 1px dashed rgba(197, 179, 142, 0.4);
  padding-top: 14px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--bg-moss);
  font-weight: 600;
}

.chapter-specs li {
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.chapter-specs li::before {
  content: "■";
  color: var(--accent-rust);
  font-size: 0.7rem;
}

/* ==========================================================================
   Section 3: Zero Token Tax Calculator (Editorial Layout)
   ========================================================================== */
.section {
  padding: 80px 0;
  border-bottom: 2px solid var(--border-taupe);
}

.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto 48px;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 2.6rem;
  color: var(--text-charcoal);
  margin-bottom: 14px;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted-dark);
}

.calc-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 36px;
  background: var(--bg-cream-card);
  border: 2px solid var(--border-taupe);
  border-radius: var(--radius-md);
  padding: 36px;
}

.calc-controls { display: flex; flex-direction: column; gap: 24px; }

.slider-group label {
  display: flex;
  justify-content: space-between;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-charcoal);
  font-family: var(--font-sans);
}

.slider-val { font-family: var(--font-mono); color: var(--accent-rust); font-weight: 700; }

input[type="range"] {
  -webkit-appearance: none;
  width: 100%; height: 8px;
  background: var(--bg-alabaster);
  border: 1px solid var(--border-taupe);
  border-radius: 4px;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px; height: 22px;
  background: var(--accent-rust);
  border: 2px solid var(--bg-alabaster);
  border-radius: 50%;
  cursor: pointer;
  transition: var(--transition-smooth);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  background: var(--accent-rust-hover);
}

.toggle-card:has(input:checked) {
  border-color: var(--accent-rust) !important;
  background: rgba(184, 93, 61, 0.06) !important;
}
.toggle-card:hover {
  border-color: var(--text-charcoal) !important;
}

.calc-results { display: flex; flex-direction: column; gap: 14px; }

.result-card {
  background: var(--bg-alabaster);
  border: 1.5px solid var(--border-taupe);
  border-radius: var(--radius-sm);
  padding: 18px;
  text-align: center;
}

.result-title {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted-dark);
  text-transform: uppercase;
  margin-bottom: 6px;
}

.result-number { font-family: var(--font-serif); font-size: 2.1rem; font-weight: 700; }
.result-number.legacy { color: #A04E31; text-decoration: line-through; opacity: 0.75; }
.result-number.saving { color: var(--bg-moss); }

/* ==========================================================================
   Section 6: Neuro-Assist Floating Dock (Retro Brass)
   ========================================================================== */
.neuro-dock {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 2000;
}

.dock-trigger {
  width: 56px;
  height: 56px;
  background: var(--accent-rust);
  color: var(--bg-alabaster);
  border: 2px solid var(--border-taupe);
  border-radius: 50%;
  font-size: 1.5rem;
  cursor: pointer;
  box-shadow: 0 8px 24px rgba(184, 93, 61, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-smooth);
}

.dock-trigger:hover {
  transform: scale(1.1) rotate(10deg);
  background: var(--accent-rust-hover);
}

.dock-menu {
  position: absolute;
  bottom: 70px;
  right: 0;
  width: 310px;
  background: var(--bg-alabaster);
  border: 2px solid var(--border-taupe);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: 0 16px 40px rgba(0,0,0,0.25);
  display: none;
  flex-direction: column;
  gap: 16px;
}

.dock-menu.open { display: flex; }

.dock-title {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.1rem;
  border-bottom: 1.5px solid var(--border-taupe);
  padding-bottom: 8px;
  color: var(--text-charcoal);
}

.dock-option {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-charcoal);
}

/* Toggle Switch */
.switch { position: relative; display: inline-block; width: 44px; height: 24px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider-round {
  position: absolute;
  cursor: pointer;
  top: 0; left: 0; right: 0; bottom: 0;
  background-color: var(--bg-cream-card);
  border: 1px solid var(--border-taupe);
  transition: .3s;
  border-radius: 34px;
}
.slider-round:before {
  position: absolute;
  content: "";
  height: 16px; width: 16px;
  left: 3px; bottom: 3px;
  background-color: var(--text-muted-dark);
  transition: .3s;
  border-radius: 50%;
}
input:checked + .slider-round { background-color: var(--accent-rust); }
input:checked + .slider-round:before {
  transform: translateX(20px);
  background-color: var(--bg-alabaster);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  background: var(--bg-moss-dark);
  color: var(--text-alabaster);
  border-top: 2px solid var(--border-taupe);
  padding: 60px 0;
  text-align: center;
}

.footer-brand {
  font-family: var(--font-serif);
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--border-taupe);
}

.footer p { color: var(--text-muted-light); max-width: 600px; margin: 0 auto; }

/* ==========================================================================
   MOBILE-FIRST RESPONSIVE PERFECTION (< 768px)
   ========================================================================== */
@media (max-width: 768px) {
  .nav-links { display: none; } /* Simplify navbar on phone */
  
  .navbar {
    padding: 10px 0;
  }
  
  .nav-content {
    flex-direction: column;
    gap: 12px;
    align-items: center;
    justify-content: center;
    text-align: center;
  }
  
  .brand {
    justify-content: center;
    width: 100%;
    gap: 6px;
    font-size: 1.1rem;
    flex-wrap: wrap;
  }
  
  .brand-logo {
    height: 20px;
    max-width: 24px;
  }
  
  .brand-icon {
    width: 28px;
    height: 28px;
    font-size: 0.85rem;
  }
  
  .nav-controls {
    width: 100%;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
  }
  
  .nav-controls .btn {
    padding: 6px 12px;
    font-size: 0.78rem;
    gap: 4px;
  }
  
  .hero-title { font-size: 2.3rem; }
  
  /* Make all floating glass panels center-aligned on mobile */
  .floating-glass-panel,
  .floating-glass-panel.align-left,
  .floating-glass-panel.align-right,
  .floating-glass-panel.align-center {
    width: 92% !important;
    max-width: 100% !important;
    align-self: center !important;
    margin: 0 auto !important;
    padding: 24px;
  }
  
  .floating-glass-layer {
    gap: 55vh;
    padding: 10vh 16px 20vh;
  }
  
  .sticky-substrate {
    top: 60px;
    height: calc(100vh - 60px);
  }
  
  .cockpit-hud-container,
  .terminal-hud-container,
  .textual-tui-container {
    width: 96%;
    height: 84%;
    padding: 0;
  }
  
  .tui-body {
    flex-direction: column;
  }
  
  .tui-sidebar {
    width: 100%;
    border-right: none;
    border-bottom: 1.5px solid var(--border-taupe);
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    padding: 8px;
    gap: 4px;
  }
  
  .tui-sidebar-title,
  .tui-sidebar-footer {
    display: none;
  }
  
  .tui-tab {
    padding: 6px 10px;
    font-size: 0.72rem;
  }
  
  .tui-console {
    padding: 14px 16px;
    font-size: 0.8rem;
  }

  .calc-grid {
    grid-template-columns: 1fr;
    padding: 18px;
  }
}