/* ==========================================================================
   AiReadCode Official Landing Page & Download Portal Stylesheet
   Theme: Obsidian Dark / Cyber Glassmorphism / Modern Engineering
   ========================================================================== */

@import url("https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500;600&family=Outfit:wght@500;600;700;800&display=swap");

:root {
  /* Color Palette */
  --bg-primary: #080a10;
  --bg-secondary: #0e121c;
  --bg-tertiary: #141926;
  --surface-card: rgba(20, 26, 40, 0.72);
  --surface-card-hover: rgba(28, 36, 56, 0.85);
  --surface-elevated: rgba(30, 41, 59, 0.6);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(99, 102, 241, 0.35);
  --border-glow: rgba(59, 130, 246, 0.5);

  /* Brand Accents & Gradients */
  --accent-blue: #3b82f6;
  --accent-cyan: #06b6d4;
  --accent-purple: #8b5cf6;
  --accent-indigo: #6366f1;
  --accent-pink: #ec4899;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;

  --gradient-brand: linear-gradient(135deg, #38bdf8 0%, #6366f1 50%, #a855f7 100%);
  --gradient-card-border: linear-gradient(135deg, rgba(255, 255, 255, 0.15) 0%, rgba(255, 255, 255, 0.02) 100%);
  --gradient-glow: radial-gradient(circle, rgba(99, 102, 241, 0.22) 0%, rgba(8, 10, 16, 0) 70%);

  /* Text Colors */
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-highlight: #e2e8f0;

  /* Typography */
  --font-sans: "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-heading: "Outfit", "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: "JetBrains Mono", Consolas, "Microsoft YaHei", Menlo, monospace;

  /* Shadows & Glass */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.65);
  --shadow-glow: 0 0 45px rgba(99, 102, 241, 0.25);
  --glass-blur: blur(20px);

  /* Layout */
  --max-width: 1240px;
  --nav-height: 72px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
}

/* ==========================================================================
   Light Theme System
   ========================================================================== */
html[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f1f5f9;
  --surface-card: rgba(255, 255, 255, 0.92);
  --surface-card-hover: rgba(255, 255, 255, 1);
  --surface-elevated: rgba(241, 245, 249, 0.95);
  --border-subtle: rgba(15, 23, 42, 0.08);
  --border-hover: rgba(99, 102, 241, 0.4);
  --border-glow: rgba(59, 130, 246, 0.3);

  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  --text-highlight: #020617;

  --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 8px 30px rgba(15, 23, 42, 0.06);
  --shadow-lg: 0 20px 60px rgba(15, 23, 42, 0.09);
  --shadow-glow: 0 0 35px rgba(99, 102, 241, 0.12);

  color-scheme: light;
}

/* Light Mode Element Overrides */
html[data-theme="light"] .site-header.scrolled {
  background: rgba(255, 255, 255, 0.88);
  border-bottom: 1px solid rgba(15, 23, 42, 0.08);
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.06);
}

html[data-theme="light"] .logo-text {
  background: linear-gradient(135deg, #0f172a 40%, #475569 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

html[data-theme="light"] .badge-version {
  background: rgba(15, 23, 42, 0.05);
  border-color: rgba(15, 23, 42, 0.08);
  color: #475569;
}

html[data-theme="light"] .btn-secondary {
  background: #ffffff;
  color: #0f172a;
  border-color: rgba(15, 23, 42, 0.12);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.05);
}

html[data-theme="light"] .btn-secondary:hover {
  background: #f1f5f9;
  border-color: rgba(15, 23, 42, 0.22);
  color: #020617;
}

html[data-theme="light"] .hero-pill {
  background: #ffffff;
  color: #334155;
  border-color: rgba(15, 23, 42, 0.08);
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
}

html[data-theme="light"] .hero-stat {
  background: #ffffff;
  border-color: rgba(15, 23, 42, 0.06);
  box-shadow: 0 4px 14px rgba(15, 23, 42, 0.03);
}

html[data-theme="light"] .hero-stat strong {
  color: #0f172a;
}

html[data-theme="light"] .hero-stat span {
  color: #64748b;
}

html[data-theme="light"] .ambient-glow-top {
  background: radial-gradient(ellipse at center, rgba(99, 102, 241, 0.1) 0%, rgba(56, 189, 248, 0.05) 45%, transparent 70%);
}

html[data-theme="light"] .ambient-glow-middle {
  background: radial-gradient(circle, rgba(168, 85, 247, 0.06) 0%, transparent 65%);
}

html[data-theme="light"] .ambient-grid {
  background-image: linear-gradient(rgba(15, 23, 42, 0.025) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(15, 23, 42, 0.025) 1px, transparent 1px);
}

html[data-theme="light"] .mockup-window {
  border-color: rgba(15, 23, 42, 0.1);
  box-shadow: 0 20px 50px rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .window-header {
  background: #f1f5f9;
  border-bottom: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .window-title {
  color: #0f172a;
}

html[data-theme="light"] .window-meta {
  color: #64748b;
}

html[data-theme="light"] .mockup-body {
  background: #ffffff;
}

html[data-theme="light"] .mockup-toc {
  background: #f8fafc;
  border-right: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .mockup-book-title {
  color: #0f172a;
}

html[data-theme="light"] .mockup-book-sub {
  color: #64748b;
}

html[data-theme="light"] .toc-item {
  color: #475569;
}

html[data-theme="light"] .toc-item:hover {
  background: rgba(15, 23, 42, 0.04);
  color: #0f172a;
}

html[data-theme="light"] .toc-item.active {
  background: rgba(99, 102, 241, 0.1);
  color: #4338ca;
}

html[data-theme="light"] .mockup-content {
  background: #ffffff;
  color: #1e293b;
}

html[data-theme="light"] .mockup-h1 {
  color: #0f172a;
}

html[data-theme="light"] .mockup-p {
  color: #334155;
}

html[data-theme="light"] .mockup-p code,
html[data-theme="light"] .demo-prose code,
html[data-theme="light"] .anatomy-lead code {
  background: #f1f5f9;
  color: #0f172a;
  border: 1px solid rgba(15, 23, 42, 0.06);
}

html[data-theme="light"] .mockup-source {
  background: #f8fafc;
  border-left: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .source-code-block {
  background: #f1f5f9;
  color: #0f172a;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .source-path {
  color: #475569;
}

html[data-theme="light"] .mockup-four-layer {
  background: #ffffff;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .four-layer-title {
  color: #0f172a;
}

html[data-theme="light"] .mockup-diagram-card {
  background: #f8fafc;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .diagram-node {
  background: #ffffff;
  color: #0f172a;
  border: 1px solid rgba(99, 102, 241, 0.3);
}

/* Interactive Demo / Reading Experience Section Light Mode */
html[data-theme="light"] .section-demo {
  background: var(--bg-tertiary);
  border-top: 1px solid rgba(15, 23, 42, 0.06);
  border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}

html[data-theme="light"] .reading-path span:not(.reading-path-arrow) {
  background: #ffffff;
  border: 1px solid rgba(15, 23, 42, 0.08);
  color: #334155;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

html[data-theme="light"] .reading-path-arrow {
  color: #94a3b8;
}

html[data-theme="light"] .demo-tab-btn {
  background: #ffffff;
  border: 1px solid rgba(15, 23, 42, 0.1);
  color: #475569;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

html[data-theme="light"] .demo-tab-btn:hover {
  background: #f8fafc;
  color: #0f172a;
  border-color: rgba(99, 102, 241, 0.3);
}

html[data-theme="light"] .demo-tab-btn.active {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.14), rgba(59, 130, 246, 0.14));
  border-color: var(--accent-indigo);
  color: #4338ca;
  box-shadow: 0 2px 10px rgba(99, 102, 241, 0.15);
}

html[data-theme="light"] .demo-display-panel {
  background: #ffffff;
  border: 1px solid rgba(15, 23, 42, 0.08);
  box-shadow: 0 15px 40px rgba(15, 23, 42, 0.06);
}

html[data-theme="light"] .demo-card-box {
  background: #f8fafc;
  border: 1px solid rgba(15, 23, 42, 0.08);
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.02);
}

html[data-theme="light"] .demo-card-code {
  background: #f1f5f9;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .demo-box-title {
  color: #0284c7;
}

html[data-theme="light"] .demo-box-title span:last-child {
  color: #64748b;
  font-weight: 500;
}

html[data-theme="light"] .demo-chapter-title {
  color: #0f172a;
}

html[data-theme="light"] .demo-prose {
  color: #334155;
}

html[data-theme="light"] .demo-prose strong {
  color: #0f172a;
}

html[data-theme="light"] .demo-prose code {
  background: #e2e8f0;
  color: #0f172a;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .fact-callout {
  background: rgba(59, 130, 246, 0.06);
  border: 1px solid rgba(59, 130, 246, 0.2);
  color: #334155;
}

html[data-theme="light"] .fact-callout strong {
  color: #1d4ed8;
}

html[data-theme="light"] .mockup-fact-tag {
  background: rgba(59, 130, 246, 0.1);
  border-color: rgba(59, 130, 246, 0.25);
  color: #1d4ed8;
}

html[data-theme="light"] .mockup-inference,
html[data-theme="light"] .demo-infer {
  color: #64748b;
}

html[data-theme="light"] .demo-infer strong {
  color: #4338ca;
}

html[data-theme="light"] .demo-note {
  color: #64748b;
}

html[data-theme="light"] .code-line-highlight {
  background: rgba(59, 130, 246, 0.12);
  border-left: 3px solid #2563eb;
  color: #0f172a;
}

html[data-theme="light"] .four-layer-tag {
  color: #4338ca;
  background: rgba(99, 102, 241, 0.06);
  padding: 2px 8px;
  border-radius: 4px;
}

html[data-theme="light"] .four-layer-text {
  color: #334155;
}

html[data-theme="light"] .prep-list {
  color: #334155;
}

html[data-theme="light"] .prep-list strong {
  color: #0f172a;
}

html[data-theme="light"] .glossary-term {
  color: #0f172a;
}

/* Additional Homepage Sections Light Mode */
html[data-theme="light"] .section-tag {
  background: rgba(99, 102, 241, 0.08);
  border-color: rgba(99, 102, 241, 0.2);
  color: #4338ca;
}

html[data-theme="light"] .section-paradigm {
  background: linear-gradient(180deg, var(--bg-primary) 0%, #f1f5f9 100%);
}

html[data-theme="light"] .section-downloads {
  background: linear-gradient(180deg, var(--bg-primary) 0%, #f1f5f9 100%);
}

html[data-theme="light"] .journey-index {
  color: #4f46e5;
}

html[data-theme="light"] .layer-feature-tags span {
  background: #f1f5f9;
  color: #475569;
  border-color: rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .card-airead .card-badge {
  background: rgba(99, 102, 241, 0.12);
  color: #4338ca;
}

html[data-theme="light"] .pricing-card.pricing-card-featured {
  background: linear-gradient(180deg, rgba(99, 102, 241, 0.06) 0%, #ffffff 100%);
}

html[data-theme="light"] .pricing-amount {
  color: #0f172a;
}

html[data-theme="light"] .os-title {
  color: #0f172a;
}

html[data-theme="light"] .faq-question {
  color: #0f172a;
}

html[data-theme="light"] .faq-answer {
  color: #334155;
}

html[data-theme="light"] .site-footer {
  background: #f1f5f9;
  border-top: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .footer-bottom {
  border-top: 1px solid rgba(15, 23, 42, 0.06);
}

html[data-theme="light"] .sec-item,
html[data-theme="light"] .device-row,
html[data-theme="light"] #sec-pwd-form,
html[data-theme="light"] #sec-bind-box {
  background: #f8fafc;
  border: 1px solid rgba(15, 23, 42, 0.08);
}

html[data-theme="light"] .device-name,
html[data-theme="light"] .sec-item-val {
  color: #0f172a;
}

html[data-theme="light"] .stack-field input,
html[data-theme="light"] .stack-field textarea,
html[data-theme="light"] .stack-field select {
  background: #ffffff;
  color: #0f172a;
  border-color: rgba(15, 23, 42, 0.15);
}

html[data-theme="light"] .slider-track {
  background: #e2e8f0;
  border-color: rgba(15, 23, 42, 0.1);
}

html[data-theme="light"] .modal-box {
  background: #ffffff;
  border-color: rgba(15, 23, 42, 0.1);
  color: #0f172a;
}

html[data-theme="light"] .auth-card {
  background: #ffffff;
  border-color: rgba(15, 23, 42, 0.1);
}

html[data-theme="light"] .auth-tab-btn {
  color: #64748b;
}

html[data-theme="light"] .auth-tab-btn.active {
  color: #4338ca;
  border-bottom-color: var(--accent-indigo);
}

/* Theme Toggle Button Style */
.theme-toggle-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.2s ease;
  padding: 0;
  flex-shrink: 0;
}

.theme-toggle-btn:hover {
  background: var(--surface-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-1px);
}

.theme-toggle-btn .icon-sun {
  display: block;
  width: 18px;
  height: 18px;
  color: #f59e0b;
}

.theme-toggle-btn .icon-moon {
  display: none;
  width: 18px;
  height: 18px;
  color: #6366f1;
}

html[data-theme="light"] .theme-toggle-btn .icon-sun {
  display: none;
}

html[data-theme="light"] .theme-toggle-btn .icon-moon {
  display: block;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-height) + 24px);
  color-scheme: dark;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
}

/* Background Atmospheric Glows */
.ambient-glow-top {
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 550px;
  background: radial-gradient(ellipse at center, rgba(99, 102, 241, 0.28) 0%, rgba(56, 189, 248, 0.12) 45%, transparent 70%);
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
}

.ambient-glow-middle {
  position: absolute;
  top: 1800px;
  right: -200px;
  width: 700px;
  height: 500px;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.16) 0%, transparent 65%);
  filter: blur(90px);
  pointer-events: none;
  z-index: 0;
}

.ambient-grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(circle at center, black, transparent 85%);
  pointer-events: none;
  z-index: 0;
}

/* Common Container */
.container {
  width: min(100% - 40px, var(--max-width));
  margin-inline: auto;
  position: relative;
  z-index: 1;
}

/* Section Header Typography */
.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.3);
  color: #a5b4fc;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.section-tag svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
}

.section-title {
  font-family: var(--font-heading);
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-desc {
  font-size: clamp(16px, 1.8vw, 18px);
  color: var(--text-secondary);
  max-width: 680px;
  margin-inline: auto;
  line-height: 1.7;
}

.text-center {
  text-align: center;
}

.text-gradient {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 100;
  transition: all 0.3s ease;
}

.site-header.scrolled {
  background: rgba(8, 10, 16, 0.82);
  backdrop-filter: var(--glass-blur);
  border-bottom: 1px solid var(--border-subtle);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

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

.logo-group {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.logo-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.logo-icon svg {
  width: 20px;
  height: 20px;
  color: #ffffff;
}

.logo-text {
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.3px;
  background: linear-gradient(135deg, #ffffff 40%, #cbd5e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.badge-version {
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Button Styles */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  border: 1px solid transparent;
  user-select: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.38);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(99, 102, 241, 0.55);
  filter: brightness(1.08);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 14px 28px;
  font-size: 16px;
  border-radius: var(--radius-md);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 24px;
  cursor: pointer;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero-section {
  padding-top: calc(var(--nav-height) + 64px);
  padding-bottom: 80px;
  text-align: center;
  position: relative;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  background: rgba(30, 41, 59, 0.6);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(12px);
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 28px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.hero-pill .pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-emerald);
  box-shadow: 0 0 10px var(--accent-emerald);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(36px, 5.8vw, 68px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -1.2px;
  max-width: 960px;
  margin-inline: auto;
  margin-bottom: 24px;
}

.hero-desc {
  font-size: clamp(17px, 2vw, 20px);
  color: var(--text-secondary);
  max-width: 760px;
  margin-inline: auto;
  margin-bottom: 38px;
  line-height: 1.7;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.platform-detect-hint {
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin-bottom: 56px;
}

.platform-detect-hint span.detected-os {
  color: var(--accent-cyan);
  font-weight: 600;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 880px;
  margin: 0 auto 48px;
  text-align: left;
}

.hero-stat {
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
}

.hero-stat strong {
  display: block;
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.4px;
  margin-bottom: 4px;
}

.hero-stat span {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.45;
}

/* Hero Interactive Mockup */
.hero-mockup-wrapper {
  position: relative;
  max-width: 1160px;
  margin-inline: auto;
  border-radius: var(--radius-lg);
  padding: 8px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.12) 0%, rgba(255, 255, 255, 0.02) 100%);
  box-shadow: 0 30px 100px rgba(0, 0, 0, 0.8), 0 0 60px rgba(99, 102, 241, 0.18);
}

.mockup-window {
  background: var(--bg-secondary);
  border-radius: calc(var(--radius-lg) - 4px);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
  text-align: left;
}

.window-header {
  height: 42px;
  background: #0f1422;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
}

.window-dots {
  display: flex;
  gap: 7px;
}

.window-dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
}
.dot-red { background: #ef4444; }
.dot-yellow { background: #f59e0b; }
.dot-green { background: #10b981; }

.window-title {
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.window-meta {
  font-size: 11px;
  color: #64748b;
}

.mockup-body {
  display: grid;
  grid-template-columns: 240px 1fr 340px;
  min-height: 520px;
  background: #0c101a;
}

/* Mockup Left Sidebar: TOC */
.mockup-toc {
  background: #090d16;
  border-right: 1px solid var(--border-subtle);
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.mockup-book-meta {
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 8px;
}

.mockup-book-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-primary);
}

.mockup-book-sub {
  font-size: 11px;
  color: var(--accent-cyan);
}

.toc-item {
  font-size: 12px;
  padding: 7px 10px;
  border-radius: 6px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: default;
}

.toc-item.active {
  background: rgba(99, 102, 241, 0.16);
  color: #c7d2fe;
  font-weight: 600;
  border-left: 3px solid var(--accent-indigo);
}

/* Mockup Center: Markdown Book Content */
.mockup-content {
  padding: 24px 30px;
  overflow-y: auto;
  border-right: 1px solid var(--border-subtle);
  background: #0c101a;
}

.mockup-h1 {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.mockup-p {
  font-size: 13px;
  color: #cbd5e1;
  line-height: 1.7;
  margin-bottom: 14px;
}

.mockup-p code,
.demo-prose code,
.anatomy-lead code,
.privacy-card code,
.trust-card-desc code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  padding: 1px 5px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.06);
}

.mockup-inference,
.demo-infer {
  color: #94a3b8;
  font-size: 12px;
}

.mockup-fact-tag {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 2px 8px;
  background: rgba(59, 130, 246, 0.15);
  border: 1px solid rgba(59, 130, 246, 0.35);
  border-radius: 4px;
  color: #60a5fa;
  font-size: 11px;
  font-family: var(--font-mono);
  font-weight: 600;
}

.mockup-diagram-card {
  margin: 16px 0;
  padding: 14px;
  border-radius: 8px;
  background: #111728;
  border: 1px solid var(--border-subtle);
  font-size: 12px;
}

.mockup-diagram-header {
  font-size: 11px;
  color: var(--text-muted);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.diagram-nodes {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 10px 0;
}

.diagram-node {
  padding: 6px 14px;
  border-radius: 6px;
  background: rgba(99, 102, 241, 0.2);
  border: 1px solid rgba(99, 102, 241, 0.4);
  color: #e0e7ff;
  font-size: 12px;
  font-weight: 600;
}

.diagram-arrow {
  color: #64748b;
  font-size: 12px;
}

/* Mockup Right: Source Code + 4-Layer Explain */
.mockup-source {
  background: #090d16;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.source-head {
  font-size: 12px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-subtle);
}

.source-head-ok {
  color: #34d399;
}

.source-caption {
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.55;
}

.source-code-block {
  font-family: var(--font-mono);
  font-size: 11px;
  background: #0d121f;
  padding: 12px;
  border-radius: 6px;
  border: 1px solid var(--border-subtle);
  line-height: 1.6;
}

.code-line-highlight {
  background: rgba(59, 130, 246, 0.18);
  display: block;
  margin: 0 -12px;
  padding: 0 12px;
  border-left: 3px solid #3b82f6;
  color: #bfdbfe;
}

.mockup-four-layer {
  background: #111728;
  border-radius: 8px;
  border: 1px solid rgba(99, 102, 241, 0.3);
  padding: 12px;
  font-size: 11px;
}

.four-layer-tag {
  font-weight: 700;
  color: #818cf8;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.four-layer-text {
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ==========================================================================
   Journey / Anatomy / Audience / Difference
   ========================================================================== */
.section-journey,
.section-anatomy,
.section-audience {
  padding: 96px 0;
}

.section-title-left {
  text-align: left;
  max-width: 560px;
}

.journey-steps {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 56px;
}

.journey-step {
  padding: 28px 22px;
  border-radius: var(--radius-md);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
}

.journey-index {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1px;
  color: #a5b4fc;
  margin-bottom: 14px;
}

.journey-step h3 {
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.journey-step p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.65;
}

.journey-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 16px;
}

.journey-chips span {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 999px;
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
}

.journey-chips span.is-on {
  color: #c7d2fe;
  border-color: rgba(99, 102, 241, 0.45);
  background: rgba(99, 102, 241, 0.18);
}

.anatomy-layout {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 56px;
  align-items: start;
}

.anatomy-lead {
  margin-top: 16px;
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 520px;
}

.anatomy-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.anatomy-list li {
  display: flex;
  gap: 14px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border-subtle);
}

.anatomy-list li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.anatomy-num {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: #c7d2fe;
  background: rgba(99, 102, 241, 0.18);
}

.anatomy-list strong {
  display: block;
  margin-bottom: 4px;
}

.anatomy-list p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.audience-grid,
.diff-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 48px;
}

.audience-card,
.diff-card {
  padding: 28px 24px;
  border-radius: var(--radius-md);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
}

.audience-card h3,
.diff-card h3 {
  font-family: var(--font-heading);
  font-size: 20px;
  margin-bottom: 10px;
}

.audience-card p,
.diff-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.65;
}

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

.diff-kicker {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.diff-ours {
  border-color: rgba(99, 102, 241, 0.4);
  box-shadow: 0 12px 40px rgba(99, 102, 241, 0.12);
}

.diff-ours .diff-kicker {
  color: #a5b4fc;
}

.reading-path {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px 10px;
  margin: 36px auto 8px;
  max-width: 860px;
  font-size: 13px;
  color: var(--text-secondary);
}

.reading-path span:not(.reading-path-arrow) {
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
}

.reading-path-arrow {
  color: var(--text-muted);
}

.demo-chapter-title {
  font-size: 18px;
  margin-bottom: 12px;
}

.demo-prose {
  font-size: 14px;
  color: #cbd5e1;
  line-height: 1.7;
  margin-bottom: 14px;
}

.fact-callout {
  margin: 0 0 14px;
  padding: 14px 16px;
  border-radius: 10px;
  background: rgba(59, 130, 246, 0.08);
  border: 1px solid rgba(59, 130, 246, 0.28);
  font-size: 13px;
  color: #cbd5e1;
}

.fact-callout p {
  margin-top: 8px;
}

.demo-note {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.6;
}

.demo-card-code {
  background: #090d16;
}

.explain-stack {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.prep-list {
  padding-left: 18px;
  color: #cbd5e1;
  font-size: 14px;
  line-height: 1.7;
}

.prep-list li + li {
  margin-top: 10px;
}

.glossary-term {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 10px;
}

.section-pricing {
  padding: 96px 0 40px;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 360px));
  justify-content: center;
  gap: 24px;
  margin-top: 48px;
}

.pricing-card {
  padding: 32px 28px;
  border-radius: var(--radius-lg);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.pricing-card-featured {
  border-color: rgba(99, 102, 241, 0.45);
  box-shadow: 0 12px 40px rgba(99, 102, 241, 0.14);
}

.pricing-badge {
  font-size: 12px;
  font-weight: 700;
  color: #a5b4fc;
}

.pricing-card h3 {
  font-family: var(--font-heading);
  font-size: 22px;
}

.pricing-amount {
  font-family: var(--font-heading);
  font-size: 40px;
  font-weight: 800;
  letter-spacing: -1px;
}

.pricing-amount span {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-muted);
}

.pricing-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 14px;
  color: var(--text-secondary);
  flex: 1;
}

.pricing-note {
  margin-top: 28px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
}

.pricing-note a {
  color: var(--accent-cyan);
  text-decoration: none;
}

.legal-page {
  padding: calc(var(--nav-height) + 48px) 0 80px;
}

.legal-page h1 {
  font-family: var(--font-heading);
  font-size: clamp(28px, 4vw, 40px);
  margin-bottom: 12px;
}

.legal-page .legal-updated {
  color: var(--text-muted);
  font-size: 13px;
  margin-bottom: 32px;
}

.legal-page h2 {
  font-family: var(--font-heading);
  font-size: 20px;
  margin: 28px 0 10px;
}

.legal-page p,
.legal-page li {
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.75;
}

.legal-page ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

.account-panel,
.feedback-form {
  max-width: 520px;
  margin: 32px auto 0;
  padding: 28px;
  border-radius: var(--radius-lg);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
}

.auth-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
}

.auth-tab {
  flex: 1;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  font-weight: 600;
}

.auth-tab.active {
  color: #fff;
  border-color: var(--accent-indigo);
  background: rgba(99, 102, 241, 0.2);
}

.stack-field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 14px;
  font-size: 13px;
  color: var(--text-secondary);
}

.stack-field input,
.stack-field select,
.stack-field textarea {
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background: #090d16;
  color: var(--text-primary);
  font: inherit;
}

.stack-field textarea {
  min-height: 140px;
  resize: vertical;
}

.form-status {
  margin-top: 14px;
  font-size: 13px;
  color: #86efac;
}

.form-status.is-error {
  color: #fca5a5;
}

.account-dashboard {
  max-width: 640px;
}

.account-dashboard ul {
  padding-left: 18px;
  margin: 8px 0 20px;
  color: var(--text-secondary);
}

.account-dashboard li {
  margin-bottom: 8px;
}

.section-privacy {
  padding: 0 0 80px;
}

.privacy-card {
  max-width: 860px;
  margin-inline: auto;
  padding: 32px 36px;
  border-radius: var(--radius-lg);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
}

.privacy-card h3 {
  font-family: var(--font-heading);
  font-size: 22px;
  margin-bottom: 10px;
}

.privacy-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.downloads-footnote {
  margin-top: 40px;
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
}

.downloads-footnote a {
  color: var(--accent-cyan);
  text-decoration: none;
}

.footer-meta {
  display: flex;
  gap: 16px;
}

.modal-emoji {
  font-size: 32px;
  margin-bottom: 12px;
}

.modal-box h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 8px;
}

.modal-box p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
}

.modal-filename {
  background: rgba(255, 255, 255, 0.05);
  padding: 12px;
  border-radius: 8px;
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 20px;
}

.modal-action {
  width: 100%;
}

/* ==========================================================================
   Paradigm Shift Section (Why AiReadCode)
   ========================================================================== */
.section-paradigm {
  padding: 100px 0;
  background: linear-gradient(180deg, var(--bg-primary) 0%, #0d111a 100%);
}

.comparison-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 50px;
}

.comparison-card {
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  position: relative;
  overflow: hidden;
  backdrop-filter: var(--glass-blur);
}

.comparison-card.card-legacy {
  border-color: rgba(239, 68, 68, 0.25);
}

.comparison-card.card-legacy::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #ef4444, transparent);
}

.comparison-card.card-airead {
  border-color: rgba(99, 102, 241, 0.4);
  box-shadow: 0 12px 40px rgba(99, 102, 241, 0.15);
}

.comparison-card.card-airead::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-brand);
}

.card-badge {
  display: inline-flex;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 20px;
}

.card-legacy .card-badge {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
}

.card-airead .card-badge {
  background: rgba(99, 102, 241, 0.2);
  color: #a5b4fc;
}

.card-heading {
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 14px;
}

.card-summary {
  color: var(--text-secondary);
  font-size: 15px;
  margin-bottom: 24px;
  line-height: 1.6;
}

.card-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.card-list li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 14px;
  color: #cbd5e1;
}

.card-list li svg {
  flex-shrink: 0;
  margin-top: 3px;
  width: 18px;
  height: 18px;
}

.card-legacy svg { color: #ef4444; }
.card-airead svg { color: #10b981; }

/* ==========================================================================
   5-Layer Cognitive System Section
   ========================================================================== */
.section-five-layers {
  padding: 100px 0;
  position: relative;
}

.layers-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 56px;
}

.layers-grid .layer-card:nth-child(4),
.layers-grid .layer-card:nth-child(5) {
  grid-column: span 1;
}

.layer-card {
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  position: relative;
}

.layer-card:hover {
  transform: translateY(-5px);
  background: var(--surface-card-hover);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-md);
}

.layer-icon-box {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.layer-1 .layer-icon-box { background: rgba(59, 130, 246, 0.15); color: #60a5fa; }
.layer-2 .layer-icon-box { background: rgba(16, 185, 129, 0.15); color: #34d399; }
.layer-3 .layer-icon-box { background: rgba(245, 158, 11, 0.15); color: #fbbf24; }
.layer-4 .layer-icon-box { background: rgba(139, 92, 246, 0.15); color: #a78bfa; }
.layer-5 .layer-icon-box { background: rgba(236, 72, 153, 0.15); color: #f472b6; }

.layer-step {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 6px;
}

.layer-title {
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.layer-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 18px;
  flex: 1;
}

.layer-feature-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.layer-feature-tags span {
  font-size: 12px;
  padding: 3px 9px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.05);
  color: #cbd5e1;
  border: 1px solid rgba(255, 255, 255, 0.06);
}

/* ==========================================================================
   Interactive Demo / Workspace Tabs
   ========================================================================== */
.section-demo {
  padding: 100px 0;
  background: #0a0e18;
}

.demo-tabs-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-top: 40px;
  margin-bottom: 30px;
  flex-wrap: wrap;
}

.demo-tab-btn {
  padding: 10px 20px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.demo-tab-btn:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.08);
}

.demo-tab-btn.active {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.25), rgba(139, 92, 246, 0.25));
  border-color: var(--accent-indigo);
  color: #ffffff;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.25);
}

.demo-display-panel {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  background: var(--bg-secondary);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  min-height: 480px;
}

.demo-tab-content {
  display: none;
  padding: 32px;
}

.demo-tab-content.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Specific Demo Content Styling */
.demo-split-view {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 28px;
}

.demo-card-box {
  background: #0f1422;
  border-radius: var(--radius-md);
  padding: 24px;
  border: 1px solid var(--border-subtle);
}

.demo-box-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ==========================================================================
   Trust & Reliability Section
   ========================================================================== */
.section-trust {
  padding: 90px 0;
}

.trust-features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 48px;
}

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

.trust-card-icon {
  font-size: 24px;
  margin-bottom: 14px;
}

.trust-card-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

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

/* ==========================================================================
   Download Center Section
   ========================================================================== */
.section-downloads {
  padding: 100px 0;
  background: linear-gradient(180deg, var(--bg-primary) 0%, #0c101a 100%);
  position: relative;
}

.downloads-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-top: 56px;
}

.download-card {
  background: var(--surface-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: all 0.3s ease;
  position: relative;
}

.download-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-lg);
  background: var(--surface-card-hover);
}

.download-card.recommended {
  border-color: var(--accent-indigo);
  box-shadow: 0 0 35px rgba(99, 102, 241, 0.2);
}

.rec-tag {
  position: absolute;
  top: -12px;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  color: #ffffff;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.os-icon {
  width: 64px;
  height: 64px;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
}

.os-title {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
}

.os-req {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.download-btn-group {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 20px;
}

.download-btn-group .btn {
  width: 100%;
}

.download-card-meta {
  font-size: 12px;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* ==========================================================================
   FAQ Section
   ========================================================================== */
.section-faq {
  padding: 90px 0;
}

.faq-list {
  max-width: 800px;
  margin-inline: auto;
  margin-top: 48px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  border-radius: var(--radius-md);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item.active {
  border-color: rgba(99, 102, 241, 0.4);
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 16px;
  font-weight: 600;
  text-align: left;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
}

.faq-icon {
  font-size: 20px;
  color: var(--text-muted);
  transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  color: var(--accent-indigo);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
}

.faq-item.active .faq-answer {
  max-height: 360px;
  padding-bottom: 20px;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  padding: 60px 0 30px;
  border-top: 1px solid var(--border-subtle);
  background: #06080d;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand {
  max-width: 320px;
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-top: 12px;
  line-height: 1.6;
}

.footer-nav-col h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.footer-nav-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-nav-col a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 13px;
  transition: color 0.2s ease;
}

.footer-nav-col a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  font-size: 13px;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 16px;
}

/* Toast / Download Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(8px);
  z-index: 999;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-overlay.active {
  display: flex;
}

.modal-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  max-width: 480px;
  width: 100%;
  text-align: center;
  box-shadow: var(--shadow-lg);
  position: relative;
}

.modal-close-btn {
  position: absolute;
  top: 16px;
  right: 16px;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 20px;
  cursor: pointer;
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-stats,
  .journey-steps,
  .anatomy-layout,
  .audience-grid,
  .diff-grid {
    grid-template-columns: 1fr 1fr;
  }
  .mockup-body {
    grid-template-columns: 200px 1fr;
  }
  .mockup-source {
    display: none;
  }
  .window-meta {
    display: none;
  }
  .downloads-grid {
    grid-template-columns: 1fr;
    max-width: 500px;
    margin-inline: auto;
  }
  .trust-features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 20px;
    right: 20px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px;
    border-radius: var(--radius-md);
    background: rgba(8, 10, 16, 0.96);
    border: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-md);
  }
  .nav-links.open {
    display: flex;
  }
  .nav-links .nav-link {
    display: block;
    padding: 12px 14px;
  }
  .mobile-menu-toggle {
    display: block;
  }
  .hero-stats,
  .journey-steps,
  .anatomy-layout,
  .audience-grid,
  .diff-grid,
  .comparison-grid,
  .demo-split-view,
  .trust-features-grid,
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .mockup-body {
    grid-template-columns: 1fr;
  }
  .mockup-toc {
    display: none;
  }
}