/* =========================================================================
   映话 (Yìnghuà) — Marketing Website Stylesheet
   Source of truth: design/design-tokens.json (D2 v1.0)
   Round 3 — 2026-08-24
   ========================================================================= */

/* -------------------------------------------------------------------------
   1. Tokens (CSS custom properties)
   ------------------------------------------------------------------------- */

:root {
  /* Brand */
  --color-brand-purple-vivid: #B57BFF;
  --color-brand-purple-mid: #8A5BFF;
  --color-brand-purple-deep: #2A1240;
  --color-brand-teal-vivid: #2DD4BF;
  --color-brand-teal-deep: #0E2A2A;

  /* Brand gradients */
  --gradient-primary: linear-gradient(135deg, #B57BFF 0%, #8A5BFF 50%, #2DD4BF 100%);
  --gradient-primary-2stop: linear-gradient(135deg, #B57BFF 0%, #2DD4BF 100%);
  --gradient-aurora-wash: linear-gradient(135deg, rgba(181, 123, 255, 0.18) 0%, rgba(45, 212, 191, 0.18) 100%);

  /* Semantic */
  --color-recording-red: #FF3B30;
  --color-warning-orange: #FF9F0A;
  --color-success-green: #34C759;
  --color-danger-red: #FF453A;

  /* Neutrals (dark default) */
  --color-near-black: #0A0A0F;
  --color-graphite: #1B1D22;
  --color-graphite-elevated: #232529;
  --color-glass-deep: rgba(10, 10, 15, 0.7);
  --color-warm-white: #F4F1EC;
  --color-warm-white-80: rgba(244, 241, 236, 0.8);
  --color-warm-white-60: rgba(244, 241, 236, 0.6);
  --color-warm-white-40: rgba(244, 241, 236, 0.4);
  --color-hairline: rgba(244, 241, 236, 0.08);
  --color-hairline-strong: rgba(244, 241, 236, 0.14);

  /* Backgrounds */
  --bg-base: var(--color-near-black);
  --bg-elevated: var(--color-graphite);
  --bg-card: rgba(27, 29, 34, 0.6);
  --bg-card-solid: var(--color-graphite);
  --bg-glass: rgba(27, 29, 34, 0.55);

  /* Text */
  --text-primary: var(--color-warm-white);
  --text-secondary: var(--color-warm-white-80);
  --text-tertiary: var(--color-warm-white-60);
  --text-quaternary: var(--color-warm-white-40);

  /* Borders */
  --border-hairline: var(--color-hairline);
  --border-hairline-strong: var(--color-hairline-strong);

  /* Spacing (8pt grid) */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 12px;
  --space-lg: 16px;
  --space-xl: 20px;
  --space-2xl: 24px;
  --space-3xl: 32px;
  --space-4xl: 40px;
  --space-5xl: 48px;
  --space-6xl: 64px;
  --space-7xl: 96px;
  --space-8xl: 128px;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 14px;
  --radius-2xl: 16px;
  --radius-button: 12px;
  --radius-circle: 50%;

  /* Typography */
  --font-display: 'Inter Display', 'SF Pro Display', system-ui, -apple-system, 'Noto Serif SC', serif;
  --font-text: 'Inter', 'SF Pro Text', system-ui, -apple-system, 'Noto Sans SC', sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;
  --font-serif-zh: 'Noto Serif SC', 'Songti SC', serif;
  --font-sans-zh: 'Noto Sans SC', 'PingFang SC', sans-serif;

  /* Sizes (1pt = 1.333px) */
  --text-caption: 12px;
  --text-body-2: 14px;
  --text-body-1: 15px;
  --text-display-2: 24px;
  --text-display-1: 32px;
  --text-hero: 56px;
  --text-hero-xl: 72px;

  /* Elevation */
  --shadow-card: 0 1px 8px rgba(0, 0, 0, 0.3);
  --shadow-panel: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-floating: 0 12px 40px rgba(0, 0, 0, 0.6);

  /* Motion */
  --ease-standard: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in: cubic-bezier(0.4, 0, 1, 1);
  --duration-instant: 80ms;
  --duration-fast: 120ms;
  --duration-normal: 220ms;
  --duration-slow: 250ms;

  /* Z-index */
  --z-base: 0;
  --z-card: 10;
  --z-nav: 100;
  --z-floating: 1000;

  /* Container */
  --container-max: 1200px;
  --container-narrow: 880px;
  --container-padding: 24px;
}

/* Light theme (overrides) */
[data-theme="light"] {
  --bg-base: #F4F1EC;
  --bg-elevated: #FFFFFF;
  --bg-card: rgba(255, 255, 255, 0.7);
  --bg-card-solid: #FFFFFF;
  --bg-glass: rgba(255, 255, 255, 0.6);

  --text-primary: #1B1D22;
  --text-secondary: rgba(27, 29, 34, 0.8);
  --text-tertiary: rgba(27, 29, 34, 0.6);
  --text-quaternary: rgba(27, 29, 34, 0.4);

  --border-hairline: rgba(27, 29, 34, 0.10);
  --border-hairline-strong: rgba(27, 29, 34, 0.18);

  --color-hairline: rgba(27, 29, 34, 0.10);
  --color-hairline-strong: rgba(27, 29, 34, 0.18);

  --color-warm-white-80: rgba(27, 29, 34, 0.8);
  --color-warm-white-60: rgba(27, 29, 34, 0.6);
  --color-warm-white-40: rgba(27, 29, 34, 0.4);

  --shadow-card: 0 1px 8px rgba(0, 0, 0, 0.08);
  --shadow-panel: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-floating: 0 12px 40px rgba(0, 0, 0, 0.18);

  --gradient-aurora-wash: linear-gradient(135deg, rgba(181, 123, 255, 0.10) 0%, rgba(45, 212, 191, 0.10) 100%);
}

@media (prefers-color-scheme: light) {
  [data-theme="auto"] {
    --bg-base: #F4F1EC;
    --bg-elevated: #FFFFFF;
    --bg-card: rgba(255, 255, 255, 0.7);
    --bg-card-solid: #FFFFFF;
    --bg-glass: rgba(255, 255, 255, 0.6);

    --text-primary: #1B1D22;
    --text-secondary: rgba(27, 29, 34, 0.8);
    --text-tertiary: rgba(27, 29, 34, 0.6);
    --text-quaternary: rgba(27, 29, 34, 0.4);

    --border-hairline: rgba(27, 29, 34, 0.10);
    --border-hairline-strong: rgba(27, 29, 34, 0.18);

    --color-hairline: rgba(27, 29, 34, 0.10);
    --color-hairline-strong: rgba(27, 29, 34, 0.18);

    --color-warm-white-80: rgba(27, 29, 34, 0.8);
    --color-warm-white-60: rgba(27, 29, 34, 0.6);
    --color-warm-white-40: rgba(27, 29, 34, 0.4);

    --shadow-card: 0 1px 8px rgba(0, 0, 0, 0.08);
    --shadow-panel: 0 8px 24px rgba(0, 0, 0, 0.12);
    --shadow-floating: 0 12px 40px rgba(0, 0, 0, 0.18);

    --gradient-aurora-wash: linear-gradient(135deg, rgba(181, 123, 255, 0.10) 0%, rgba(45, 212, 191, 0.10) 100%);
  }
}

/* -------------------------------------------------------------------------
   2. Reset + base
   ------------------------------------------------------------------------- */

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

html {
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  margin: 0;
  font-family: var(--font-text);
  font-size: var(--text-body-1);
  line-height: 1.55;
  color: var(--text-primary);
  background: var(--bg-base);
  min-height: 100vh;
  transition: background-color 250ms var(--ease-standard), color 250ms var(--ease-standard);
  font-feature-settings: 'cv11', 'ss01', 'ss03';
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 120ms var(--ease-standard);
}

a:hover { color: var(--color-brand-purple-vivid); }

button {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

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

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h1 { font-size: var(--text-hero-xl); letter-spacing: -0.035em; }
h2 { font-size: var(--text-hero); letter-spacing: -0.03em; }
h3 { font-size: var(--text-display-1); }
h4 { font-size: var(--text-display-2); }
h5 { font-size: 20px; }

p { margin: 0; }

ul, ol { margin: 0; padding: 0; list-style: none; }

::selection {
  background: var(--color-brand-purple-mid);
  color: var(--color-warm-white);
}

/* -------------------------------------------------------------------------
   3. Layout helpers
   ------------------------------------------------------------------------- */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.container-narrow {
  width: 100%;
  max-width: var(--container-narrow);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.section {
  padding-top: var(--space-7xl);
  padding-bottom: var(--space-7xl);
  position: relative;
}

.section-divider {
  border-top: 1px solid var(--border-hairline);
}

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-brand-teal-vivid);
  margin-bottom: var(--space-lg);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto var(--space-6xl);
}

.section-header h2 {
  margin-bottom: var(--space-lg);
}

.section-header p {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.55;
}

.text-gradient {
  background: var(--gradient-primary-2stop);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* -------------------------------------------------------------------------
   4. Navigation
   ------------------------------------------------------------------------- */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-nav);
  background: var(--bg-glass);
  -webkit-backdrop-filter: blur(40px) saturate(180%);
  backdrop-filter: blur(40px) saturate(180%);
  border-bottom: 1px solid var(--border-hairline);
  transition: background 250ms var(--ease-standard), border-color 250ms var(--ease-standard);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: var(--space-2xl);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 17px;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.nav-brand img {
  width: 32px;
  height: 32px;
  border-radius: 7.17px; /* 22.4% of 32 */
  display: block;
}

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

.nav-brand .brand-zh {
  font-family: var(--font-serif-zh);
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-2xl);
  flex: 1;
  justify-content: center;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: 6px 2px;
  transition: color 120ms var(--ease-standard);
}

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

.nav-links a.active {
  color: var(--text-primary);
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: var(--gradient-primary-2stop);
  border-radius: 2px;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Theme toggle */
.theme-toggle {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-circle);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: background 120ms var(--ease-standard), color 120ms var(--ease-standard);
}

.theme-toggle:hover {
  background: var(--color-hairline);
  color: var(--text-primary);
}

.theme-toggle svg { width: 18px; height: 18px; }

.theme-toggle .icon-light { display: none; }
.theme-toggle .icon-dark { display: block; }

[data-theme="light"] .theme-toggle .icon-light { display: block; }
[data-theme="light"] .theme-toggle .icon-dark { display: none; }

/* Mobile nav */
.nav-mobile-toggle {
  display: none;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-circle);
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
}

.nav-mobile-toggle:hover {
  background: var(--color-hairline);
  color: var(--text-primary);
}

.nav-mobile-menu {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border-hairline);
  padding: var(--space-2xl) var(--container-padding);
  z-index: calc(var(--z-nav) - 1);
  -webkit-backdrop-filter: blur(40px) saturate(180%);
  backdrop-filter: blur(40px) saturate(180%);
}

.nav-mobile-menu.open { display: block; }

.nav-mobile-menu a {
  display: block;
  padding: 12px 0;
  font-size: 16px;
  color: var(--text-primary);
  border-bottom: 1px solid var(--border-hairline);
}

.nav-mobile-menu a:last-child { border-bottom: 0; }

/* -------------------------------------------------------------------------
   5. Buttons
   ------------------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  height: 44px;
  padding: 0 var(--space-xl);
  border-radius: var(--radius-button);
  font-family: var(--font-text);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: -0.01em;
  cursor: pointer;
  transition: transform 120ms var(--ease-spring), box-shadow 120ms var(--ease-standard), background 120ms var(--ease-standard), color 120ms var(--ease-standard), border-color 120ms var(--ease-standard);
  user-select: none;
  white-space: nowrap;
}

.btn:active { transform: scale(0.98); transition: transform 80ms var(--ease-in); }

.btn-primary {
  background: var(--gradient-primary-2stop);
  color: #0A0A0F;
  font-weight: 600;
  box-shadow: 0 4px 16px rgba(181, 123, 255, 0.25);
}

.btn-primary:hover {
  color: #0A0A0F;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(181, 123, 255, 0.35);
}

.btn-primary:active { transform: scale(0.98) translateY(0); }

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

.btn-secondary:hover {
  background: var(--color-hairline);
  color: var(--text-primary);
}

.btn-ghost {
  color: var(--text-secondary);
  padding: 0 var(--space-md);
  height: 36px;
  font-size: 14px;
}

.btn-ghost:hover { color: var(--text-primary); background: var(--color-hairline); }

.btn-lg { height: 52px; padding: 0 var(--space-2xl); font-size: 16px; }

.btn-sm { height: 36px; padding: 0 var(--space-lg); font-size: 14px; }

.btn .icon-arrow {
  width: 14px;
  height: 14px;
  margin-left: 2px;
  transition: transform 120ms var(--ease-standard);
}

.btn-primary:hover .icon-arrow,
.btn-secondary:hover .icon-arrow { transform: translate(2px, -2px); }

/* -------------------------------------------------------------------------
   6. Hero
   ------------------------------------------------------------------------- */

.hero {
  position: relative;
  padding: calc(var(--space-8xl) + 64px) 0 var(--space-7xl);
  overflow: hidden;
  isolation: isolate;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(ellipse 80% 50% at 30% 0%, rgba(181, 123, 255, 0.20), transparent 70%),
    radial-gradient(ellipse 70% 50% at 70% 30%, rgba(45, 212, 191, 0.18), transparent 70%),
    var(--bg-base);
  transition: background 400ms var(--ease-standard);
}

[data-theme="light"] .hero-bg,
[data-theme="auto"] .hero-bg {
  background:
    radial-gradient(ellipse 80% 50% at 30% 0%, rgba(181, 123, 255, 0.12), transparent 70%),
    radial-gradient(ellipse 70% 50% at 70% 30%, rgba(45, 212, 191, 0.10), transparent 70%),
    var(--bg-base);
}

.hero-noise {
  position: absolute;
  inset: 0;
  z-index: -1;
  opacity: 0.4;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0.95 0 0 0 0 0.95 0 0 0 0 0.95 0 0 0 0.03 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mix-blend-mode: overlay;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: var(--space-6xl);
  align-items: center;
  position: relative;
}

.hero-content {
  max-width: 560px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  height: 32px;
  padding: 0 var(--space-md);
  border-radius: var(--radius-circle);
  background: var(--bg-card);
  border: 1px solid var(--border-hairline);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: var(--space-2xl);
}

.hero-badge .pulse {
  width: 6px;
  height: 6px;
  border-radius: var(--radius-circle);
  background: var(--color-recording-red);
  animation: pulse 1400ms var(--ease-standard) infinite;
}

[data-theme="light"] .hero-badge .pulse { box-shadow: 0 0 0 2px rgba(255, 59, 48, 0.18); }

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.3); opacity: 0.6; }
}

.hero h1 {
  font-size: clamp(44px, 7vw, 80px);
  font-weight: 700;
  letter-spacing: -0.04em;
  margin-bottom: var(--space-xl);
  line-height: 1.02;
}

.hero h1 .brand-zh {
  font-family: var(--font-serif-zh);
  font-weight: 600;
  letter-spacing: -0.06em;
}

.hero h1 .brand-en {
  display: block;
  font-size: 0.42em;
  font-weight: 500;
  color: var(--text-tertiary);
  letter-spacing: 0.04em;
  margin-top: var(--space-md);
  font-family: var(--font-mono);
  text-transform: uppercase;
}

.hero-tagline {
  font-family: var(--font-serif-zh);
  font-size: clamp(20px, 2.2vw, 26px);
  font-weight: 400;
  color: var(--text-secondary);
  line-height: 1.45;
  margin-bottom: var(--space-3xl);
  letter-spacing: 0;
}

.hero-cta-row {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
}

.hero-microcopy {
  font-size: 13px;
  color: var(--text-tertiary);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.hero-microcopy span:not(:last-child)::after {
  content: '·';
  margin-left: var(--space-sm);
  color: var(--text-quaternary);
}

.hero-visual {
  position: relative;
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-floating);
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  transform: perspective(1500px) rotateY(-3deg) rotateX(2deg);
  transition: transform 600ms var(--ease-standard);
}

.hero-visual:hover { transform: perspective(1500px) rotateY(-1deg) rotateX(1deg); }

.hero-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.hero-visual::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 60%, rgba(10, 10, 15, 0.4));
  pointer-events: none;
}

/* -------------------------------------------------------------------------
   7. Features
   ------------------------------------------------------------------------- */

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-2xl);
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-hairline);
  border-radius: var(--radius-2xl);
  padding: var(--space-3xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  position: relative;
  overflow: hidden;
  transition: border-color 220ms var(--ease-standard), transform 220ms var(--ease-standard);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--color-hairline);
}

.feature-card:hover {
  border-color: var(--border-hairline-strong);
  transform: translateY(-2px);
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-lg);
  background: var(--gradient-aurora-wash);
  border: 1px solid var(--border-hairline);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-brand-purple-vivid);
}

.feature-icon svg { width: 28px; height: 28px; }

.feature-card h3 {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin: 0;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.6;
}

.feature-meta {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-top: auto;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border-hairline);
  font-size: 12px;
  font-family: var(--font-mono);
  color: var(--text-tertiary);
  letter-spacing: 0.02em;
}

.feature-meta .dot {
  width: 4px;
  height: 4px;
  border-radius: var(--radius-circle);
  background: var(--color-success-green);
}

.feature-visual {
  height: 140px;
  border-radius: var(--radius-lg);
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  position: relative;
  overflow: hidden;
  margin-top: var(--space-sm);
}

.feature-visual::after {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-aurora-wash);
  opacity: 0.4;
}

/* -------------------------------------------------------------------------
   8. Product preview (App Store screenshots)
   ------------------------------------------------------------------------- */

.screenshots-row {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: var(--space-xl);
  align-items: end;
}

.screenshot-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  align-items: center;
}

.screenshot-frame {
  width: 100%;
  aspect-ratio: 16 / 10;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  box-shadow: var(--shadow-card);
  transition: transform 220ms var(--ease-standard), box-shadow 220ms var(--ease-standard);
}

.screenshot-frame:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-panel);
}

.screenshot-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
}

.screenshot-label {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  text-align: center;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.screenshot-caption {
  font-size: 12px;
  color: var(--text-tertiary);
  text-align: center;
  margin-top: 2px;
}

/* -------------------------------------------------------------------------
   9. For Teams
   ------------------------------------------------------------------------- */

.teams-grid {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: var(--space-6xl);
  align-items: center;
}

.teams-content h2 {
  font-size: clamp(36px, 5vw, 56px);
  margin-bottom: var(--space-xl);
  line-height: 1.05;
}

.teams-content p {
  font-size: 17px;
  color: var(--text-secondary);
  margin-bottom: var(--space-3xl);
  line-height: 1.6;
}

.teams-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  margin-bottom: var(--space-3xl);
}

.teams-list li {
  display: flex;
  gap: var(--space-md);
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.55;
}

.teams-list .check {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  border-radius: var(--radius-circle);
  background: var(--gradient-aurora-wash);
  border: 1px solid var(--border-hairline-strong);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-brand-teal-vivid);
  margin-top: 1px;
}

.teams-list .check svg { width: 12px; height: 12px; }

.teams-visual {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.teams-card {
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  box-shadow: var(--shadow-card);
  transition: transform 220ms var(--ease-standard), box-shadow 220ms var(--ease-standard);
}

.teams-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-panel);
}

.teams-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.teams-card .teams-card-label {
  padding: var(--space-md) var(--space-lg);
  font-size: 12px;
  font-family: var(--font-mono);
  color: var(--text-tertiary);
  letter-spacing: 0.02em;
  border-top: 1px solid var(--border-hairline);
  text-align: center;
}

/* -------------------------------------------------------------------------
   10. Pricing
   ------------------------------------------------------------------------- */

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-2xl);
  align-items: stretch;
}

.price-card {
  background: var(--bg-card);
  border: 1px solid var(--border-hairline);
  border-radius: var(--radius-2xl);
  padding: var(--space-3xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-xl);
  position: relative;
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  transition: border-color 220ms var(--ease-standard);
}

.price-card.featured {
  border-color: var(--color-brand-purple-mid);
  background: linear-gradient(180deg, rgba(181, 123, 255, 0.06), transparent 50%), var(--bg-card);
}

.price-card.featured::before {
  content: '推荐';
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-primary-2stop);
  color: #0A0A0F;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 4px var(--space-md);
  border-radius: var(--radius-circle);
  font-family: var(--font-mono);
}

.price-tier {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-brand-teal-vivid);
}

.price-amount {
  display: flex;
  align-items: baseline;
  gap: var(--space-sm);
}

.price-amount .currency {
  font-size: 22px;
  color: var(--text-secondary);
  font-weight: 500;
}

.price-amount .value {
  font-family: var(--font-display);
  font-size: 56px;
  font-weight: 700;
  letter-spacing: -0.04em;
  color: var(--text-primary);
  line-height: 1;
}

.price-amount .period {
  font-size: 15px;
  color: var(--text-tertiary);
  font-family: var(--font-mono);
}

.price-description {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.5;
  margin-top: -8px;
}

.price-features {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  flex: 1;
}

.price-features li {
  display: flex;
  gap: var(--space-sm);
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
}

.price-features .check {
  flex-shrink: 0;
  color: var(--color-brand-teal-vivid);
  margin-top: 3px;
}

.price-features .check svg { width: 14px; height: 14px; }

.price-cta {
  margin-top: var(--space-sm);
}

.price-cta .btn { width: 100%; }

/* -------------------------------------------------------------------------
   11. FAQ
   ------------------------------------------------------------------------- */

.faq {
  max-width: 760px;
  margin: 0 auto;
}

.faq-item {
  border-top: 1px solid var(--border-hairline);
}

.faq-item:last-child {
  border-bottom: 1px solid var(--border-hairline);
}

.faq-trigger {
  width: 100%;
  text-align: left;
  padding: var(--space-2xl) 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-lg);
  font-size: 17px;
  font-weight: 500;
  color: var(--text-primary);
  transition: color 120ms var(--ease-standard);
}

.faq-trigger:hover { color: var(--color-brand-purple-vivid); }

.faq-trigger .icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  color: var(--text-tertiary);
  transition: transform 220ms var(--ease-standard);
}

.faq-item.open .faq-trigger .icon {
  transform: rotate(45deg);
  color: var(--color-brand-purple-vivid);
}

.faq-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 280ms var(--ease-standard);
}

.faq-item.open .faq-content {
  max-height: 500px;
}

.faq-content-inner {
  padding-bottom: var(--space-2xl);
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.6;
}

/* -------------------------------------------------------------------------
   12. Footer
   ------------------------------------------------------------------------- */

.footer {
  background: var(--bg-elevated);
  border-top: 1px solid var(--border-hairline);
  padding: var(--space-6xl) 0 var(--space-3xl);
  margin-top: var(--space-7xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: var(--space-5xl);
  margin-bottom: var(--space-5xl);
}

.footer-brand {
  max-width: 280px;
}

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

.footer-col h4 {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: var(--space-lg);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer-col a {
  font-size: 14px;
  color: var(--text-secondary);
}

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

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border-hairline);
  font-size: 12px;
  color: var(--text-tertiary);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.footer-socials {
  display: flex;
  gap: var(--space-md);
}

.footer-socials a {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-circle);
  background: var(--bg-card);
  border: 1px solid var(--border-hairline);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: color 120ms var(--ease-standard), background 120ms var(--ease-standard);
}

.footer-socials a:hover {
  color: var(--text-primary);
  background: var(--color-hairline);
}

.footer-socials svg { width: 16px; height: 16px; }

/* -------------------------------------------------------------------------
   13. Generic page styles
   ------------------------------------------------------------------------- */

.page-hero {
  padding: calc(var(--space-8xl) + 64px) 0 var(--space-6xl);
  text-align: center;
  position: relative;
  overflow: hidden;
  isolation: isolate;
}

.page-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 600px;
  background: radial-gradient(circle at center, rgba(181, 123, 255, 0.20), transparent 70%);
  z-index: -1;
  pointer-events: none;
}

.page-hero h1 {
  font-size: clamp(40px, 5.5vw, 64px);
  margin-bottom: var(--space-xl);
  letter-spacing: -0.04em;
}

.page-hero p {
  font-size: 19px;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
  line-height: 1.55;
}

.prose {
  max-width: 720px;
  margin: 0 auto;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-secondary);
}

.prose h2 {
  font-size: 28px;
  margin-top: var(--space-6xl);
  margin-bottom: var(--space-lg);
  letter-spacing: -0.02em;
}

.prose h3 {
  font-size: 20px;
  margin-top: var(--space-4xl);
  margin-bottom: var(--space-md);
}

.prose p, .prose ul, .prose ol {
  margin-bottom: var(--space-lg);
}

.prose ul, .prose ol {
  padding-left: 24px;
  list-style: disc;
}

.prose ol { list-style: decimal; }

.prose li {
  margin-bottom: var(--space-sm);
}

.prose a {
  color: var(--color-brand-purple-vivid);
  border-bottom: 1px solid currentColor;
}

.prose a:hover { color: var(--color-brand-teal-vivid); }

.prose strong { color: var(--text-primary); font-weight: 600; }

.prose code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  background: var(--color-hairline);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
}

/* -------------------------------------------------------------------------
   14. Download page
   ------------------------------------------------------------------------- */

.download-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-5xl);
  align-items: start;
  margin-top: var(--space-5xl);
}

.download-card {
  background: var(--bg-card);
  border: 1px solid var(--border-hairline);
  border-radius: var(--radius-2xl);
  padding: var(--space-4xl);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
}

.download-card h2 {
  font-size: 32px;
  margin-bottom: var(--space-md);
}

.download-card .version {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-tertiary);
  margin-bottom: var(--space-2xl);
  letter-spacing: 0.04em;
}

.download-card .checksum {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-tertiary);
  background: var(--bg-base);
  border: 1px solid var(--border-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  word-break: break-all;
  margin-top: var(--space-lg);
}

.requirements {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.requirement-item {
  display: flex;
  gap: var(--space-md);
  align-items: flex-start;
}

.requirement-item .req-icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--gradient-aurora-wash);
  border: 1px solid var(--border-hairline);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--color-brand-teal-vivid);
}

.requirement-item .req-icon svg { width: 20px; height: 20px; }

.requirement-item h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 2px;
}

.requirement-item p {
  font-size: 14px;
  color: var(--text-secondary);
}

.known-issues {
  margin-top: var(--space-4xl);
}

.known-issues h3 {
  font-size: 20px;
  margin-bottom: var(--space-lg);
}

.known-issues ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.known-issues li {
  display: flex;
  gap: var(--space-sm);
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.55;
}

.known-issues li::before {
  content: '◦';
  color: var(--color-warning-orange);
  font-weight: 700;
  flex-shrink: 0;
}

/* -------------------------------------------------------------------------
   15. Detailed features page
   ------------------------------------------------------------------------- */

.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6xl);
  align-items: center;
  margin-bottom: var(--space-7xl);
}

.feature-block:nth-child(even) { direction: rtl; }
.feature-block:nth-child(even) > * { direction: ltr; }

.feature-block-visual {
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  background: var(--bg-elevated);
  border: 1px solid var(--border-hairline);
  box-shadow: var(--shadow-card);
}

.feature-block-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.feature-block-content h2 {
  font-size: 40px;
  margin-bottom: var(--space-lg);
  letter-spacing: -0.03em;
}

.feature-block-content .lede {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: var(--space-2xl);
  line-height: 1.55;
}

.feature-block-content ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.feature-block-content li {
  display: flex;
  gap: var(--space-md);
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.55;
}

.feature-block-content li .check {
  flex-shrink: 0;
  color: var(--color-brand-teal-vivid);
  margin-top: 2px;
}

.feature-block-content li .check svg { width: 16px; height: 16px; }

.feature-block-content li strong { color: var(--text-primary); font-weight: 600; }

/* -------------------------------------------------------------------------
   16. Comparison table
   ------------------------------------------------------------------------- */

.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  margin-top: var(--space-3xl);
}

.compare-table th, .compare-table td {
  padding: var(--space-md) var(--space-lg);
  text-align: left;
  border-bottom: 1px solid var(--border-hairline);
}

.compare-table th {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-tertiary);
}

.compare-table td:first-child { font-weight: 500; color: var(--text-primary); }

.compare-table th:not(:first-child),
.compare-table td:not(:first-child) { text-align: center; }

.compare-table .check-yes { color: var(--color-success-green); }
.compare-table .check-no { color: var(--text-quaternary); }
.compare-table .check-maybe { color: var(--color-warning-orange); font-family: var(--font-mono); font-size: 12px; }

.compare-table tr:last-child td { border-bottom: 0; }

/* -------------------------------------------------------------------------
   17. Responsive — 1440 / 1024 / 768 / 375
   ------------------------------------------------------------------------- */

/* Large desktops: 1440px+ (default) */

/* Laptops: ≤ 1024px */
@media (max-width: 1024px) {
  :root {
    --text-hero: 48px;
    --text-hero-xl: 60px;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: var(--space-5xl);
  }

  .hero-visual {
    aspect-ratio: 16 / 10;
    max-width: 720px;
    margin: 0 auto;
    transform: none;
  }

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

  .screenshots-row {
    grid-template-columns: repeat(3, 1fr);
  }

  .screenshots-row .screenshot-card:nth-child(n+4) {
    display: none;
  }

  .teams-grid {
    grid-template-columns: 1fr;
    gap: var(--space-4xl);
  }

  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }

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

  .feature-block {
    grid-template-columns: 1fr;
    gap: var(--space-3xl);
  }

  .feature-block:nth-child(even) { direction: ltr; }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
  }
}

/* Tablets: ≤ 768px */
@media (max-width: 768px) {
  :root {
    --container-padding: 20px;
    --space-7xl: 72px;
    --space-8xl: 96px;
  }

  .nav-links { display: none; }
  .nav-mobile-toggle { display: inline-flex; }
  .nav-actions .btn-ghost { display: none; }

  .hero {
    padding: calc(var(--space-7xl) + 64px) 0 var(--space-6xl);
  }

  .hero h1 { font-size: clamp(36px, 9vw, 52px); }
  .hero-tagline { font-size: 18px; }

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

  .screenshots-row {
    grid-template-columns: repeat(3, 1fr);
  }

  .section-header h2 { font-size: 36px; }
  .section-header p { font-size: 16px; }

  .pricing-card { padding: var(--space-2xl); }
  .price-amount .value { font-size: 44px; }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-3xl);
  }

  .footer-bottom {
    flex-direction: column;
    gap: var(--space-lg);
    align-items: flex-start;
  }

  .compare-table {
    font-size: 13px;
  }

  .compare-table th, .compare-table td {
    padding: var(--space-sm) var(--space-md);
  }
}

/* Phones: ≤ 480px */
@media (max-width: 480px) {
  :root {
    --container-padding: 16px;
    --space-7xl: 56px;
    --space-8xl: 80px;
  }

  .nav { background: var(--bg-elevated); }

  .nav-brand .brand-name { display: none; }

  .hero-badge { font-size: 12px; padding: 0 12px; height: 28px; }

  .hero-cta-row { flex-direction: column; align-items: stretch; }
  .hero-cta-row .btn { width: 100%; }

  .hero-microcopy { flex-wrap: wrap; row-gap: 4px; }

  .section { padding-top: var(--space-6xl); padding-bottom: var(--space-6xl); }
  .section-header { margin-bottom: var(--space-4xl); }
  .section-header h2 { font-size: 30px; }

  .feature-card { padding: var(--space-2xl); }
  .feature-block-content h2 { font-size: 28px; }
  .teams-content h2 { font-size: 32px; }

  .screenshots-row { gap: var(--space-md); }
  .screenshot-frame { border-radius: var(--radius-lg); }

  .teams-visual { grid-template-columns: 1fr; gap: var(--space-md); }

  .price-card { padding: var(--space-xl); }
  .price-amount .value { font-size: 40px; }

  .download-card { padding: var(--space-2xl); }
}

/* -------------------------------------------------------------------------
   18. Reduced motion
   ------------------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  html { scroll-behavior: auto; }

  .hero-visual { transform: none !important; }
  .feature-card:hover, .screenshot-frame:hover, .teams-card:hover { transform: none !important; }

  .pulse { animation: none !important; }
}

/* -------------------------------------------------------------------------
   19. Print
   ------------------------------------------------------------------------- */

@media print {
  .nav, .footer, .nav-mobile-toggle, .theme-toggle, .nav-actions { display: none; }
  body { background: #fff; color: #000; }
}

/* -------------------------------------------------------------------------
   20. Accessibility — skip link + focus rings
   ------------------------------------------------------------------------- */

/* Skip link: hidden until focused, jumps to #main */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: #B57BFF;
  color: #ffffff;
  padding: 8px 16px;
  z-index: 1000;
  text-decoration: none;
  border-radius: 0 0 8px 0;
  font-weight: 600;
  font-size: 14px;
  transition: top 0.15s ease-out;
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 0;
  outline: 2px solid #ffffff;
  outline-offset: -4px;
}

/* Visible focus rings for keyboard navigation only (mouse users see :focus) */
*:focus-visible {
  outline: 2px solid #B57BFF;
  outline-offset: 4px;
  border-radius: 4px;
}
button:focus-visible,
a:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline-offset: 2px;
}

/* Ensure interactive elements always have a focus style */
button:focus,
a:focus,
input:focus,
textarea:focus,
select:focus {
  outline: none;
}