/* ============================================================
   GPWS Documentation & Manual — Global Design System
   ============================================================ */

:root {
  --bg-primary: #080c14;
  --bg-secondary: #0f172a;
  --bg-card: #131d31;
  --bg-card-hover: #1a2742;
  --border-color: #1e2d4a;
  --border-color-glow: rgba(0, 230, 118, 0.3);

  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  --accent-green: #00e676;
  --accent-green-glow: rgba(0, 230, 118, 0.25);
  --accent-yellow: #ffd600;
  --accent-yellow-glow: rgba(255, 214, 0, 0.25);
  --accent-red: #ff1744;
  --accent-red-glow: rgba(255, 23, 68, 0.25);
  --accent-blue: #38bdf8;
  --accent-blue-glow: rgba(56, 189, 248, 0.25);

  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 30px var(--accent-green-glow);

  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  color-scheme: dark;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-green);
}

/* Utility Classes */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

.text-gradient {
  background: linear-gradient(135deg, #ffffff 0%, var(--accent-green) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-green {
  color: var(--accent-green);
}

.text-yellow {
  color: var(--accent-yellow);
}

.text-red {
  color: var(--accent-red);
}

.text-blue {
  color: var(--accent-blue);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.badge-green {
  background: rgba(0, 230, 118, 0.12);
  color: var(--accent-green);
  border: 1px solid rgba(0, 230, 118, 0.3);
}

.badge-yellow {
  background: rgba(255, 214, 0, 0.12);
  color: var(--accent-yellow);
  border: 1px solid rgba(255, 214, 0, 0.3);
}

.badge-red {
  background: rgba(255, 23, 68, 0.12);
  color: var(--accent-red);
  border: 1px solid rgba(255, 23, 68, 0.3);
}

.badge-blue {
  background: rgba(56, 189, 248, 0.12);
  color: var(--accent-blue);
  border: 1px solid rgba(56, 189, 248, 0.3);
}

/* Header & Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(8, 12, 20, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: var(--transition);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: 1px;
}

.brand-icon {
  width: 36px;
  height: 36px;
  /* background: linear-gradient(135deg, var(--accent-green), #00b0ff); */
  background: linear-gradient(135deg, #ffffff, var(--accent-green));
  /* background: white; */
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #080c14;
  font-size: 1.1rem;
  font-weight: 900;
  box-shadow: 0 0 16px var(--accent-green-glow);
}

.nav-links {
  display: flex;
  gap: 28px;
  list-style: none;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent-green);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-green);
  transition: var(--transition);
  border-radius: 2px;
}

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

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

.btn-primary {
  background: var(--accent-green);
  color: #080c14;
  box-shadow: 0 0 20px var(--accent-green-glow);
}

.btn-primary:hover {
  background: #00ff84;
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(0, 230, 118, 0.4);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-green);
  color: var(--accent-green);
  transform: translateY(-2px);
}

/* Mobile Menu Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero Section */
.hero {
  padding: 140px 0 80px;
  position: relative;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--accent-green-glow) 0%, rgba(8, 12, 20, 0) 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: 3.25rem;
  font-weight: 800;
  line-height: 1.15;
  margin: 16px 0 20px;
  letter-spacing: -1px;
}

.hero-subtitle {
  font-size: 1.125rem;
  color: var(--text-muted);
  margin-bottom: 32px;
  max-width: 540px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-media {
  position: relative;
}

.hero-img-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  position: relative;
  transition: var(--transition);
}

.hero-img-wrapper:hover {
  border-color: var(--accent-green);
  box-shadow: 0 0 35px var(--accent-green-glow);
}

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

/* Stats / Highlight Cards */
.stats-bar {
  padding: 40px 0;
  background: var(--bg-secondary);
  border-y: 1px solid var(--border-color);
  margin-bottom: 80px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 24px;
  border-radius: var(--radius-md);
  text-align: center;
  transition: var(--transition);
}

.stat-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-green);
}

.stat-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent-green);
  font-family: var(--font-mono);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Section Styling */
.section {
  padding: 80px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 56px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  margin: 12px 0;
  letter-spacing: -0.5px;
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* Feature Cards Grid */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: var(--transition);
  position: relative;
}

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

.card-icon {
  width: 48px;
  height: 48px;
  background: rgba(0, 230, 118, 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-green);
  font-size: 1.5rem;
  margin-bottom: 20px;
  border: 1px solid rgba(0, 230, 118, 0.2);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.card-text {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Architecture Showcase */
.arch-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

.arch-img-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

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

.board-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 20px;
  transition: var(--transition);
}

.board-card:hover {
  border-color: var(--accent-blue);
}

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

.board-title {
  font-size: 1.15rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 10px;
}

.mac-address {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  background: #080c14;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  color: var(--accent-blue);
  border: 1px solid var(--border-color);
}

.board-list {
  list-style: none;
}

.board-list li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.board-list li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--accent-green);
  font-weight: bold;
}

/* Alert Levels & Table */
.alert-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 40px;
}

.table-responsive {
  width: 100%;
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}

.data-table th {
  background: var(--bg-secondary);
  padding: 14px 18px;
  color: var(--text-main);
  font-weight: 600;
  border-bottom: 1px solid var(--border-color);
  white-space: nowrap;
}

.data-table td {
  padding: 14px 18px;
  color: var(--text-muted);
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

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

.data-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

/* Audio Player Section */
.audio-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.track-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: var(--transition);
}

.track-card:hover {
  border-color: var(--accent-green);
  transform: translateY(-2px);
}

.track-num {
  width: 40px;
  height: 40px;
  background: #080c14;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--accent-green);
}

.track-info {
  flex: 1;
}

.track-name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-main);
}

.track-trigger {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 2px;
}

/* Callout Box */
.callout {
  background: rgba(56, 189, 248, 0.08);
  border-left: 4px solid var(--accent-blue);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 24px 0;
  font-size: 0.925rem;
  color: var(--text-main);
}

.callout-warning {
  background: rgba(255, 214, 0, 0.08);
  border-left-color: var(--accent-yellow);
}

.callout-danger {
  background: rgba(255, 23, 68, 0.08);
  border-left-color: var(--accent-red);
}

/* Code Snippets */
.code-wrapper {
  background: #060911;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  margin: 20px 0;
}

.code-header {
  background: var(--bg-secondary);
  padding: 10px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.8rem;
}

.code-content {
  padding: 16px;
  overflow-x: auto;
  color: #e2e8f0;
  line-height: 1.5;
}

/* Web Portal Box */
.portal-card {
  background: linear-gradient(145deg, #0f172a, #131d31);
  border: 1px solid var(--border-color-glow);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: 0 0 40px rgba(0, 230, 118, 0.1);
}

.portal-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
}

/* OLED Simulation Component */
.oled-container {
  background: #000;
  border: 4px solid #1e293b;
  border-radius: 12px;
  padding: 16px;
  width: 100%;
  max-width: 320px;
  margin: 0 auto;
  box-shadow: 0 0 20px rgba(0, 230, 118, 0.2);
  font-family: 'JetBrains Mono', monospace;
}

.oled-screen {
  background: #04080c;
  color: #00e676;
  border: 1px solid #00e676;
  padding: 12px;
  border-radius: 4px;
  min-height: 140px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.oled-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  border-bottom: 1px solid rgba(0, 230, 118, 0.4);
  padding-bottom: 6px;
}

.oled-row {
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  margin: 4px 0;
}

.oled-banner {
  background: #00e676;
  color: #04080c;
  text-align: center;
  font-weight: bold;
  padding: 4px;
  font-size: 0.75rem;
  margin-top: 6px;
  border-radius: 2px;
}

/* Interactive Alert Simulator Controls */
.sim-controls {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 24px;
  border-radius: var(--radius-md);
  margin-top: 24px;
}

.sim-slider-group {
  margin-bottom: 18px;
}

.sim-slider-group label {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.sim-slider {
  width: 100%;
  accent-color: var(--accent-green);
  cursor: pointer;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 32px;
  margin-top: 80px;
  color: var(--text-muted);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  font-size: 0.9rem;
  margin-top: 12px;
  max-width: 320px;
}

.footer-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--accent-green);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  font-size: 0.85rem;
}

/* ============================================================
   Responsive Styles & Mobile Optimization
   ============================================================ */

/* Mobile Menu Toggle Button */
.mobile-toggle {
  display: none;
  background: rgba(19, 29, 49, 0.8);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  font-size: 1.15rem;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.mobile-toggle:hover,
.mobile-toggle:focus {
  border-color: var(--accent-green);
  color: var(--accent-green);
  box-shadow: 0 0 12px var(--accent-green-glow);
}

/* Tablet & Mobile Screens (<= 992px) */
@media (max-width: 992px) {
  .navbar .container {
    height: 64px;
  }

  .mobile-toggle {
    display: inline-flex;
  }

  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    width: 100%;
    background: rgba(8, 12, 20, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    gap: 0;
    padding: 12px 0;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
  }

  .nav-links.mobile-open {
    max-height: 400px;
    opacity: 1;
    visibility: visible;
    padding: 16px 0;
  }

  .nav-links li {
    width: 100%;
  }

  .nav-link {
    display: block;
    padding: 12px 24px;
    font-size: 1rem;
    border-left: 3px solid transparent;
  }

  .nav-link::after {
    display: none;
  }

  .nav-link:hover,
  .nav-link.active {
    background: rgba(0, 230, 118, 0.08);
    border-left-color: var(--accent-green);
  }

  .hero {
    padding: 110px 0 50px;
  }

  .hero-grid,
  .arch-grid,
  .alert-layout,
  .portal-grid,
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .cards-grid {
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
  }

  .portal-card {
    padding: 28px 20px;
  }
}

/* Medium Phones & Tablets (<= 768px) */
@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }

  .hero {
    padding: 96px 0 40px;
    text-align: center;
  }

  .hero-title {
    font-size: 2.15rem;
    letter-spacing: -0.5px;
  }

  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
    font-size: 0.95rem;
  }

  .hero-actions {
    justify-content: center;
    flex-direction: column;
    gap: 12px;
  }

  .hero-actions .btn {
    width: 100%;
    padding: 12px 20px;
  }

  .stats-bar {
    padding: 24px 0;
    margin-bottom: 48px;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .stat-card {
    padding: 16px 12px;
  }

  .stat-value {
    font-size: 1.5rem;
  }

  .stat-label {
    font-size: 0.75rem;
  }

  .section {
    padding: 56px 0;
  }

  .section-header {
    margin-bottom: 36px;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .section-desc {
    font-size: 0.95rem;
  }

  .card {
    padding: 20px;
  }

  .board-card {
    padding: 18px;
  }

  .board-title {
    font-size: 1rem;
  }

  /* Table Touch Scroll Support */
  .table-responsive {
    -webkit-overflow-scrolling: touch;
    margin-bottom: 24px;
    border-radius: var(--radius-sm);
  }

  .data-table th,
  .data-table td {
    padding: 10px 12px;
    font-size: 0.825rem;
  }

  .audio-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .track-card {
    padding: 14px 16px;
  }

  .callout {
    padding: 14px 16px;
    font-size: 0.875rem;
  }

  .oled-container {
    max-width: 100%;
  }

  .sim-controls {
    padding: 16px;
  }

  .footer-grid {
    gap: 28px;
  }

  .footer {
    padding: 36px 0 24px;
    margin-top: 56px;
  }
}

/* Small Phones (<= 480px) */
@media (max-width: 480px) {
  .brand span {
    font-size: 1.05rem;
  }

  .brand-icon {
    width: 32px;
    height: 32px;
    font-size: 0.95rem;
  }

  .nav-cta .btn-primary {
    padding: 8px 12px;
    font-size: 0.8rem;
  }

  .hero-title {
    font-size: 1.85rem;
  }

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

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

  .data-table {
    font-size: 0.775rem;
  }

  .data-table th,
  .data-table td {
    padding: 8px 10px;
  }

  .badge {
    font-size: 0.7rem;
    padding: 3px 10px;
  }

  .code-content pre {
    font-size: 0.775rem;
  }
}