/* ==========================================================================
   AIQA PTE LIMITED — Official Website Stylesheet
   Theme: High-Tech Enterprise (Dark, Light, System Modes)
   Fully Optimized for Desktop, Tablet, and Mobile
   ========================================================================== */

/* --------------------------------------------------------------------------
   Design Tokens & Color Modes
   -------------------------------------------------------------------------- */
:root {
  /* Default: Dark Obsidian Tech Theme */
  --bg-main: #07090E;
  --bg-surface: #0E131F;
  --bg-card: #121A2B;
  --bg-card-hover: #172238;
  --bg-glass: rgba(14, 19, 31, 0.85);
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(0, 240, 255, 0.4);
  --border-glow: rgba(99, 102, 241, 0.35);

  --accent-cyan: #00F0FF;
  --accent-cyan-glow: rgba(0, 240, 255, 0.15);
  --accent-indigo: #6366F1;
  --accent-purple: #8B5CF6;
  --accent-emerald: #10B981;

  --text-primary: #FFFFFF;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  --text-highlight: #E2E8F0;

  --nav-bg: rgba(7, 9, 14, 0.82);
  --nav-border: rgba(255, 255, 255, 0.08);
  --card-featured-bg: linear-gradient(180deg, rgba(14, 25, 45, 0.85) 0%, rgba(14, 19, 31, 0.95) 100%);
  --footer-bg: #05070B;
  --input-bg: rgba(7, 9, 14, 0.8);
  --metrics-bg: rgba(7, 9, 14, 0.6);
  --verification-bg: linear-gradient(135deg, rgba(14, 25, 45, 0.9) 0%, rgba(10, 14, 23, 0.95) 100%);
  --pill-bg: rgba(255, 255, 255, 0.04);
  --pill-cyan-bg: rgba(0, 240, 255, 0.08);
  --pill-cyan-border: rgba(0, 240, 255, 0.3);

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

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 30px rgba(0, 240, 255, 0.15);

  --btn-primary-bg: linear-gradient(135deg, #00F0FF 0%, #3B82F6 100%);
  --btn-primary-text: #060910;
  --btn-primary-shadow: rgba(0, 240, 255, 0.25);
}

/* Light Mode Overrides */
[data-theme="light"] {
  --bg-main: #F8FAFC;
  --bg-surface: #FFFFFF;
  --bg-card: #FFFFFF;
  --bg-card-hover: #F1F5F9;
  --bg-glass: rgba(255, 255, 255, 0.92);
  
  --border-subtle: #E2E8F0;
  --border-focus: #0284C7;
  --border-glow: rgba(2, 132, 199, 0.2);

  --accent-cyan: #0284C7; /* Accessible deep cyan-blue for light mode */
  --accent-cyan-glow: rgba(2, 132, 199, 0.1);
  --accent-indigo: #4F46E5;
  --accent-purple: #7C3AED;
  --accent-emerald: #059669;

  --text-primary: #0F172A;
  --text-secondary: #475569;
  --text-muted: #64748B;
  --text-highlight: #1E293B;

  --nav-bg: rgba(255, 255, 255, 0.88);
  --nav-border: #E2E8F0;
  --card-featured-bg: linear-gradient(180deg, #F0F9FF 0%, #FFFFFF 100%);
  --footer-bg: #F1F5F9;
  --input-bg: #FFFFFF;
  --metrics-bg: #F8FAFC;
  --verification-bg: linear-gradient(135deg, #F0F9FF 0%, #F8FAFC 100%);
  --pill-bg: #F1F5F9;
  --pill-cyan-bg: #E0F2FE;
  --pill-cyan-border: #BAE6FD;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 6px 20px rgba(15, 23, 42, 0.06);
  --shadow-glow: 0 4px 20px rgba(2, 132, 199, 0.12);

  --btn-primary-bg: linear-gradient(135deg, #0284C7 0%, #2563EB 100%);
  --btn-primary-text: #FFFFFF;
  --btn-primary-shadow: rgba(2, 132, 199, 0.28);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background-color: var(--bg-main);
  color: var(--text-secondary);
  font-family: var(--font-sans);
  line-height: 1.6;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.07) 0%, transparent 40%),
    radial-gradient(circle at 85% 30%, rgba(0, 240, 255, 0.05) 0%, transparent 45%);
  background-attachment: fixed;
  transition: background-color 0.25s ease, color 0.25s ease;
}

[data-theme="light"] body {
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 85% 30%, rgba(2, 132, 199, 0.04) 0%, transparent 45%);
}

.bg-grid {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 800px;
  background-size: 40px 40px;
  background-image: 
    linear-gradient(to right, rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  mask-image: linear-gradient(to bottom, black 30%, transparent 100%);
  pointer-events: none;
  z-index: 0;
}

[data-theme="light"] .bg-grid {
  background-image: 
    linear-gradient(to right, rgba(15, 23, 42, 0.03) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(15, 23, 42, 0.03) 1px, transparent 1px);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

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

.container {
  width: 100%;
  max-width: 1220px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.gradient-text {
  background: linear-gradient(135deg, #FFFFFF 20%, #00F0FF 70%, #818CF8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

[data-theme="light"] .gradient-text {
  background: linear-gradient(135deg, #0F172A 20%, #0284C7 70%, #4F46E5 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

/* --------------------------------------------------------------------------
   Header & Navigation
   -------------------------------------------------------------------------- */
.header {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: 100;
  background: var(--nav-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--nav-border);
  transition: background 0.25s, border-color 0.25s;
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 19px;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  flex-shrink: 0;
}

.brand-badge {
  font-size: 10px;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: var(--radius-sm);
  background: var(--pill-cyan-bg);
  color: var(--accent-cyan);
  border: 1px solid var(--pill-cyan-border);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

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

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
}

.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
}

.nav-link.active {
  position: relative;
  font-weight: 600;
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-cyan);
  border-radius: 2px;
}

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

/* --------------------------------------------------------------------------
   Theme Switcher Segmented Control
   -------------------------------------------------------------------------- */
.theme-switch {
  display: inline-flex;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 3px;
  gap: 2px;
}

.theme-opt {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
}

.theme-opt:hover {
  color: var(--text-primary);
}

.theme-opt.active {
  background: var(--accent-cyan);
  color: #060910;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.2);
}

[data-theme="light"] .theme-opt.active {
  color: #FFFFFF;
}

/* --------------------------------------------------------------------------
   Mobile Menu & Toggle Button
   -------------------------------------------------------------------------- */
.mobile-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  cursor: pointer;
  position: relative;
  align-items: center;
  justify-content: center;
}

.mobile-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  position: absolute;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.mobile-toggle span:nth-child(1) { transform: translateY(-5px); }
.mobile-toggle span:nth-child(2) { transform: translateY(0); }
.mobile-toggle span:nth-child(3) { transform: translateY(5px); }

.mobile-toggle.active span:nth-child(1) { transform: rotate(45deg); }
.mobile-toggle.active span:nth-child(2) { opacity: 0; }
.mobile-toggle.active span:nth-child(3) { transform: rotate(-45deg); }

/* Mobile Menu Overlay Drawer */
.mobile-drawer {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: 99;
  flex-direction: column;
  padding: 24px;
  overflow-y: auto;
  border-bottom: 1px solid var(--border-subtle);
  transform: translateY(-10px);
  opacity: 0;
  pointer-events: none;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.mobile-drawer.open {
  display: flex;
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 28px;
}

.mobile-nav-item a {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
}

.mobile-nav-item a.active {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

.mobile-theme-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  margin-bottom: 20px;
}

.mobile-theme-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.mobile-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 24px;
}

.mobile-drawer-footer {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  font-size: 12px;
  color: var(--text-muted);
  text-align: center;
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.btn-sm {
  padding: 6px 14px;
  font-size: 13px;
}

.btn-lg {
  padding: 13px 26px;
  font-size: 15px;
  border-radius: var(--radius-lg);
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  border: none;
  box-shadow: 0 4px 18px var(--btn-primary-shadow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px var(--btn-primary-shadow);
}

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

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}

[data-theme="light"] .btn-secondary:hover {
  border-color: #94A3B8;
}

.btn-ghost {
  background: transparent;
  color: var(--accent-cyan);
  padding: 8px 0;
  font-weight: 500;
}

.btn-ghost:hover {
  color: var(--text-primary);
  transform: translateX(4px);
}

/* --------------------------------------------------------------------------
   Badges & Pills
   -------------------------------------------------------------------------- */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.03em;
  background: var(--pill-bg);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  max-width: 100%;
}

.pill-cyan {
  background: var(--pill-cyan-bg);
  border-color: var(--pill-cyan-border);
  color: var(--accent-cyan);
}

.pill-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
  flex-shrink: 0;
}

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

.hero-pill-wrap {
  display: flex;
  justify-content: center;
  margin-bottom: 22px;
}

.hero-title {
  font-size: clamp(32px, 5.2vw, 54px);
  font-weight: 800;
  line-height: 1.18;
  margin-bottom: 20px;
  max-width: 960px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle {
  font-size: clamp(15px, 2vw, 19px);
  color: var(--text-secondary);
  max-width: 740px;
  margin: 0 auto 34px;
  font-weight: 400;
  line-height: 1.6;
}

.hero-cta-group {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  margin-bottom: 44px;
  flex-wrap: wrap;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  max-width: 860px;
  margin: 0 auto;
}

.hero-tag {
  font-size: 13px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-highlight);
  display: flex;
  align-items: center;
  gap: 6px;
}

/* --------------------------------------------------------------------------
   Stats Section
   -------------------------------------------------------------------------- */
.stats-section {
  padding: 30px 0 60px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
  text-align: center;
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
}

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

.stat-num {
  font-size: clamp(28px, 3.5vw, 38px);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 6px;
  letter-spacing: -0.03em;
}

.stat-num span {
  color: var(--accent-cyan);
}

.stat-label {
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
}

/* --------------------------------------------------------------------------
   Sections & Tracks
   -------------------------------------------------------------------------- */
.section {
  padding: 76px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 740px;
  margin: 0 auto 50px;
}

.section-eyebrow {
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 10px;
}

.section-title {
  font-size: clamp(26px, 3.6vw, 36px);
  margin-bottom: 14px;
}

.section-desc {
  font-size: 15px;
  color: var(--text-secondary);
}

/* Tracks Grid */
.tracks-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.track-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 32px 26px;
  position: relative;
  display: flex;
  flex-direction: column;
  transition: all 0.25s ease;
}

.track-card.featured {
  border-color: rgba(0, 240, 255, 0.35);
  background: var(--card-featured-bg);
  box-shadow: 0 10px 30px rgba(0, 240, 255, 0.08);
}

.track-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent-cyan);
}

.track-tag {
  align-self: flex-start;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 18px;
}

.track-tag.flagship {
  background: var(--pill-cyan-bg);
  color: var(--accent-cyan);
  border: 1px solid var(--pill-cyan-border);
}

.track-tag.secondary {
  background: rgba(99, 102, 241, 0.12);
  color: var(--accent-indigo);
  border: 1px solid rgba(99, 102, 241, 0.25);
}

.track-tag.base {
  background: var(--pill-bg);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
}

.track-icon {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-md);
  background: var(--pill-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  border: 1px solid var(--border-subtle);
  color: var(--accent-cyan);
  flex-shrink: 0;
}

.track-title {
  font-size: 20px;
  margin-bottom: 10px;
}

.track-desc {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 20px;
  min-height: 40px;
}

.track-list {
  list-style: none;
  margin-bottom: 26px;
  flex-grow: 1;
}

.track-list li {
  font-size: 13.5px;
  color: var(--text-highlight);
  margin-bottom: 12px;
  display: flex;
  align-items: flex-start;
  gap: 10px;
  line-height: 1.5;
}

.track-list li svg {
  flex-shrink: 0;
  margin-top: 3px;
  color: var(--accent-cyan);
}

/* --------------------------------------------------------------------------
   Why AIQA Grid
   -------------------------------------------------------------------------- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transition: all 0.25s ease;
}

.feature-box:hover {
  border-color: var(--accent-indigo);
  transform: translateY(-4px);
  background: var(--bg-card-hover);
}

.feature-icon-wrap {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: rgba(99, 102, 241, 0.12);
  color: var(--accent-indigo);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.feature-title {
  font-size: 18px;
  margin-bottom: 8px;
}

.feature-text {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   Case Studies Grid
   -------------------------------------------------------------------------- */
.cases-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.case-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
}

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

.case-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
  flex-wrap: wrap;
  gap: 8px;
}

.case-cat {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--accent-cyan);
  letter-spacing: 0.06em;
}

.case-id {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-muted);
}

.case-title {
  font-size: 19px;
  margin-bottom: 10px;
}

.case-desc {
  font-size: 13.5px;
  color: var(--text-secondary);
  margin-bottom: 18px;
  flex-grow: 1;
  line-height: 1.6;
}

.case-metrics-bar {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  background: var(--metrics-bg);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  margin-bottom: 18px;
  border: 1px solid var(--border-subtle);
}

.metric-item-num {
  font-size: 16px;
  font-weight: 700;
  color: var(--accent-emerald);
}

.metric-item-label {
  font-size: 10px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tech-tag {
  font-size: 11px;
  font-family: var(--font-mono);
  background: var(--pill-bg);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 3px 8px;
  color: var(--text-highlight);
}

/* --------------------------------------------------------------------------
   Process Steps
   -------------------------------------------------------------------------- */
.process-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
}

.process-step {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 22px 18px;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.step-duration {
  font-size: 10px;
  background: var(--pill-bg);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
}

.step-title {
  font-size: 15px;
  margin-bottom: 6px;
}

.step-desc {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Engineering Standards
   -------------------------------------------------------------------------- */
.standards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.standard-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px 20px;
}

.standard-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.standard-header svg {
  color: var(--accent-cyan);
}

.standard-title {
  font-size: 16px;
}

.standard-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   Corporate Verification Box (US Filing Focus)
   -------------------------------------------------------------------------- */
.verification-box {
  background: var(--verification-bg);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 40px;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 36px;
  align-items: center;
  box-shadow: var(--shadow-md);
}

.entity-details {
  list-style: none;
}

.entity-details li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  font-size: 13.5px;
  gap: 16px;
}

.entity-details li:last-child {
  border-bottom: none;
}

.entity-details span:first-child {
  color: var(--text-muted);
}

.entity-details span:last-child {
  color: var(--text-primary);
  font-weight: 500;
  text-align: right;
}

/* --------------------------------------------------------------------------
   Contact Info Panel
   -------------------------------------------------------------------------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 36px;
}

.contact-info-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 32px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 24px;
}

.contact-icon {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  background: var(--pill-cyan-bg);
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.contact-label {
  font-size: 11px;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-bottom: 3px;
  letter-spacing: 0.04em;
}

.contact-val {
  font-size: 14.5px;
  color: var(--text-primary);
  font-weight: 500;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
  border-top: 1px solid var(--border-subtle);
  background: var(--footer-bg);
  padding: 50px 0 28px;
  font-size: 13.5px;
  transition: background 0.25s, border-color 0.25s;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 36px;
  margin-bottom: 40px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 13.5px;
  max-width: 320px;
  margin-top: 12px;
  line-height: 1.6;
}

.footer-col-title {
  color: var(--text-primary);
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

.footer-links li {
  margin-bottom: 9px;
}

.footer-links a {
  color: var(--text-muted);
}

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

.footer-bottom {
  border-top: 1px solid var(--border-subtle);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 12px;
  flex-wrap: wrap;
  gap: 14px;
}

/* --------------------------------------------------------------------------
   Responsive Breakpoints & Mobile Optimization
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 40px;
  }
  .tracks-grid, .features-grid {
    grid-template-columns: 1fr;
  }
  .cases-grid {
    grid-template-columns: 1fr;
  }
  .process-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .standards-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .verification-box {
    grid-template-columns: 1fr;
    padding: 30px;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  /* Container tighter margins on mobile */
  .container {
    padding: 0 16px;
  }

  /* Header & Navigation */
  .nav-wrap {
    height: 64px;
  }
  .nav-links, .nav-actions .btn {
    display: none;
  }
  .mobile-toggle {
    display: flex;
  }
  .mobile-drawer {
    top: 64px;
  }

  /* Hero Section Mobile */
  .hero {
    padding: 44px 0 36px;
  }
  .hero-pill-wrap {
    margin-bottom: 16px;
  }
  .hero-title {
    font-size: 29px;
    line-height: 1.22;
    margin-bottom: 14px;
  }
  .hero-subtitle {
    font-size: 15px;
    margin-bottom: 24px;
  }
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
    gap: 12px;
    margin-bottom: 32px;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
  .hero-tags {
    gap: 8px;
  }
  .hero-tag {
    font-size: 11.5px;
    padding: 5px 12px;
  }

  /* Stats Grid Mobile */
  .stats-section {
    padding: 20px 0 40px;
  }
  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 10px;
  }
  .stat-card {
    padding: 16px 12px;
  }
  .stat-num {
    font-size: 24px;
    margin-bottom: 4px;
  }
  .stat-label {
    font-size: 11px;
    line-height: 1.3;
  }

  /* Sections Spacing */
  .section {
    padding: 48px 0;
  }
  .section-header {
    margin-bottom: 36px;
  }
  .section-title {
    font-size: 24px;
  }
  .section-desc {
    font-size: 14px;
  }

  /* Cards Mobile Padding */
  .track-card {
    padding: 22px 18px;
    border-radius: var(--radius-lg);
  }
  .track-title {
    font-size: 18px;
  }
  .track-desc {
    min-height: auto;
    font-size: 13px;
  }

  .feature-box {
    padding: 20px 16px;
    border-radius: var(--radius-md);
  }
  .feature-title {
    font-size: 16px;
  }

  .case-card {
    padding: 20px 16px;
    border-radius: var(--radius-lg);
  }
  .case-title {
    font-size: 17px;
  }
  .case-metrics-bar {
    padding: 8px 12px;
  }
  .metric-item-num {
    font-size: 15px;
  }

  .process-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }
  .process-step {
    padding: 18px 16px;
  }

  .standards-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }
  .standard-card {
    padding: 18px 16px;
  }

  /* Corporate Box Stack */
  .verification-box {
    padding: 24px 18px;
    border-radius: var(--radius-lg);
    gap: 24px;
  }
  .entity-details li {
    flex-direction: column;
    align-items: flex-start;
    gap: 2px;
  }
  .entity-details span:last-child {
    text-align: left;
    color: var(--accent-cyan);
  }

  /* 联系信息在移动端的显示 */
  .contact-info-panel {
    padding: 22px 18px;
    border-radius: var(--radius-lg);
  }
  .contact-val {
    font-size: 13.5px;
    word-break: break-word;
  }

  /* Footer Mobile */
  .footer {
    padding: 40px 0 24px;
  }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
    gap: 14px;
  }
}

@media (max-width: 480px) {
  .pill {
    font-size: 11px;
    padding: 5px 10px;
  }
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }
  .case-metrics-bar {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}