/*
 * VoxHook homepage — "Swiss-editorial light, AI-native instrument panel".
 * White-first premium surface. Depth from a three-weight border system and a
 * five-step OKLCH shadow ramp — never dark boxes. The brand blue→iris→violet
 * spectrum is treated like precious metal: brand mark, exactly one headline
 * word, SVG strokes/fills, and <12%-alpha atmosphere only. Charcoal is action,
 * gradient is identity — buttons never wear the gradient. A Space-Grotesk mono
 * voice stamps kickers, spec chips and metrics. Compositor-only motion, gated
 * behind prefers-reduced-motion. Shared by /index.html, /zh/ and /download/.
 */
:root {
  color-scheme: light;

  /* ---- surfaces : white-dominant, off-white rhythm ---- */
  --bg: oklch(0.994 0.0015 270);
  --bg-tint: oklch(0.984 0.004 270);
  --bg-muted: oklch(0.971 0.004 270);
  --card: oklch(1 0 0);
  --glass: oklch(1 0 0 / 0.66);
  --glass-strong: oklch(1 0 0 / 0.82);

  /* ---- borders : depth from three weights ---- */
  --border: oklch(0.912 0.004 270);
  --border-soft: oklch(0.946 0.003 270);
  --border-strong: oklch(0.85 0.006 270);

  /* ---- ink ramp : refined near-black, never #000 ---- */
  --heading: oklch(0.205 0.018 272);
  --ink: oklch(0.285 0.014 272);
  --ink-soft: oklch(0.435 0.012 272);
  --muted-fg: oklch(0.485 0.013 272);

  /* ---- charcoal : primary action (not the gradient) ---- */
  --char: oklch(0.225 0.014 272);
  --char-hover: oklch(0.3 0.014 272);

  /* ---- brand spectrum : blue → iris → violet ---- */
  --brand-blue: oklch(0.62 0.19 250);
  --brand-iris: oklch(0.52 0.22 277);
  --brand-violet: oklch(0.56 0.22 300);
  --brand-grad: linear-gradient(100deg, var(--brand-blue) 0%, var(--brand-iris) 52%, var(--brand-violet) 100%);

  /* ---- accent : iris family, used sparingly ---- */
  --accent: var(--brand-iris);
  --accent-strong: oklch(0.47 0.22 277);
  --accent-2: var(--brand-blue);
  --accent-soft: oklch(0.52 0.22 277 / 0.1);
  --accent-line: oklch(0.52 0.22 277 / 0.22);

  /* ---- accent washes for meshes (all < 12% alpha) ---- */
  --wash-blue: oklch(0.62 0.19 250 / 0.08);
  --wash-iris: oklch(0.52 0.22 277 / 0.1);
  --wash-violet: oklch(0.56 0.22 300 / 0.07);

  /* ---- semantic ---- */
  --ok: oklch(0.66 0.15 152);
  --ok-ring: oklch(0.66 0.15 152 / 0.16);

  --radius-sm: 0.55rem;
  --radius: 0.85rem;
  --radius-lg: 1.25rem;
  --radius-xl: 1.85rem;
  --radius-pill: 999px;

  --shadow-xs: 0 1px 2px oklch(0.2 0.02 272 / 0.05);
  --shadow-sm: 0 1px 3px oklch(0.2 0.02 272 / 0.06), 0 1px 2px -1px oklch(0.2 0.02 272 / 0.05);
  --shadow: 0 4px 14px -3px oklch(0.2 0.02 272 / 0.09), 0 2px 6px -2px oklch(0.2 0.02 272 / 0.06);
  --shadow-md: 0 14px 32px -10px oklch(0.2 0.02 272 / 0.13);
  --shadow-lg: 0 30px 64px -26px oklch(0.2 0.02 272 / 0.2);
  --shadow-brand: 0 32px 70px -30px oklch(0.52 0.22 277 / 0.34);

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out: cubic-bezier(0.22, 0.61, 0.36, 1);

  --font: Inter, "Noto Sans SC", ui-sans-serif, system-ui, -apple-system,
    BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "Space Grotesk", "Noto Sans SC", ui-monospace, "SFMono-Regular",
    "Roboto Mono", monospace;
  --container: 1180px;

  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-weight: 440;
  line-height: 1.6;
  letter-spacing: -0.006em;
}
a {
  color: inherit;
  text-decoration: none;
}
img,
svg {
  display: block;
  max-width: 100%;
}
h1,
h2,
h3,
p {
  margin: 0;
}
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
  /* white separator so the ring clears 3:1 on charcoal/gradient surfaces too */
  box-shadow: 0 0 0 2px var(--card), 0 0 0 4px var(--accent);
}
::selection {
  background: var(--accent);
  color: #fff;
}

/* ---------- layout primitives ---------- */
.container {
  width: min(var(--container), calc(100vw - 48px));
  margin: 0 auto;
}
.site {
  overflow-x: clip;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent-strong);
}
.kicker::before {
  content: "";
  width: 1.6rem;
  height: 1px;
  background: currentColor;
  opacity: 0.55;
}

.lead {
  color: var(--muted-fg);
  font-size: clamp(1.04rem, 1rem + 0.3vw, 1.15rem);
  line-height: 1.75;
}

.grad-text,
.accent {
  background: var(--brand-grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  /* guards the descenders of gradient text from clipping */
  padding-bottom: 0.06em;
}

/* mono spec chip — the AI-native "instrument" voice */
.spec {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--ink-soft);
}

/* ---------- sections + chapter washes ---------- */
.section {
  position: relative;
  padding: clamp(4.5rem, 3rem + 7vw, 8.5rem) 0;
}
/* keep anchored sections clear of the fixed nav on jump */
section[id] {
  scroll-margin-top: 5.5rem;
}
.section.is-tight {
  padding: clamp(3.5rem, 2.5rem + 4vw, 6rem) 0;
}
.section.is-muted {
  background: var(--bg-muted);
  border-top: 1px solid var(--border-soft);
  border-bottom: 1px solid var(--border-soft);
}
.section.is-blue {
  --sec-wash: var(--wash-blue);
}
.section.is-iris {
  --sec-wash: var(--wash-iris);
}
.section.is-violet {
  --sec-wash: var(--wash-violet);
}
.section[class*="is-b"]::before,
.section[class*="is-i"]::before,
.section[class*="is-v"]::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background: radial-gradient(42% 52% at 85% 0%, var(--sec-wash), transparent 64%);
}
.section > .container {
  position: relative;
  z-index: 1;
}
.section.is-cta {
  background:
    radial-gradient(46% 70% at 84% 10%, var(--wash-violet), transparent 62%),
    radial-gradient(40% 60% at 8% 95%, var(--wash-blue), transparent 64%),
    var(--bg-tint);
  border-top: 1px solid var(--border-soft);
}

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(280px, 0.62fr);
  gap: 3.5rem;
  align-items: end;
  margin-bottom: 3.5rem;
}

h2 {
  max-width: 18ch;
  margin-top: 1.1rem;
  font-size: clamp(1.95rem, 1rem + 3vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -0.032em;
  font-weight: 700;
  color: var(--heading);
  text-wrap: balance;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  height: 2.85rem;
  padding: 0 1.35rem;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1;
  white-space: nowrap;
  cursor: pointer;
  transition: background 180ms var(--ease), border-color 180ms var(--ease),
    color 180ms var(--ease), box-shadow 220ms var(--ease), transform 180ms var(--ease);
}
.btn:active {
  transform: translateY(1px) scale(0.99);
}
.btn-primary {
  background: var(--char);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover {
  background: var(--char-hover);
  box-shadow: var(--shadow), 0 12px 26px -12px oklch(0.52 0.22 277 / 0.5);
  transform: translateY(-1px);
}
.btn-outline {
  border-color: var(--border-strong);
  background: var(--card);
  color: var(--ink);
}
.btn-outline:hover {
  background: var(--bg-muted);
  border-color: oklch(0.78 0.01 272);
}
.btn-lg {
  height: 3.15rem;
  padding: 0 1.7rem;
  font-size: 0.98rem;
}
.btn svg {
  width: 1.1rem;
  height: 1.1rem;
  flex: 0 0 auto;
}

/* ---------- badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  height: 1.85rem;
  padding: 0 0.8rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  background: var(--card);
  color: var(--ink-soft);
  font-size: 0.78rem;
  font-weight: 600;
  line-height: 1;
  box-shadow: var(--shadow-xs);
}
.badge-dot::before {
  content: "";
  width: 0.42rem;
  height: 0.42rem;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 3px var(--ok-ring);
}

/* ---------- brand monogram ---------- */
.brand-mark {
  width: 1.95rem;
  height: 1.95rem;
  border-radius: 0.6rem;
  flex: 0 0 auto;
  filter: drop-shadow(0 4px 10px oklch(0.52 0.22 277 / 0.28));
}

/* ---------- nav ---------- */
.nav {
  position: fixed;
  z-index: 40;
  inset: 0 0 auto 0;
  border-bottom: 1px solid transparent;
  transition: background 240ms var(--ease), border-color 240ms var(--ease),
    backdrop-filter 240ms var(--ease);
}
.nav.is-scrolled {
  background: oklch(1 0 0 / 0.72);
  border-color: var(--border);
  backdrop-filter: saturate(180%) blur(18px);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  height: 4.5rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.04rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--heading);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}
.nav-links a {
  display: inline-flex;
  align-items: center;
  height: 2.35rem;
  padding: 0 0.85rem;
  border-radius: var(--radius-pill);
  color: var(--ink-soft);
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  transition: background 160ms var(--ease), color 160ms var(--ease);
}
.nav-links a:hover {
  color: var(--heading);
  background: var(--bg-muted);
}
.nav-cta-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.nav-cta-group .btn {
  height: 2.55rem;
  padding: 0 1.1rem;
  font-size: 0.86rem;
}

/* ---------- hero ---------- */
.hero {
  position: relative;
  padding: clamp(7.5rem, 6rem + 7vw, 10.5rem) 0 clamp(4rem, 3rem + 5vw, 6.5rem);
  color: var(--ink);
  background: linear-gradient(180deg, var(--bg-tint) 0%, var(--bg) 64%);
  isolation: isolate;
  border-bottom: 1px solid var(--border-soft);
}
.hero-glow {
  position: absolute;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(40% 44% at 88% 2%, var(--wash-iris), transparent 60%),
    radial-gradient(38% 50% at 4% 18%, var(--wash-blue), transparent 60%),
    radial-gradient(48% 60% at 70% 116%, var(--wash-violet), transparent 70%);
}
.hero-glow::after {
  content: "";
  position: absolute;
  inset: -20%;
  background: radial-gradient(36% 36% at 60% 40%, var(--accent-soft), transparent 70%);
  opacity: 0.7;
}
.hero-grid {
  position: absolute;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(oklch(0.2 0.02 272 / 0.032) 1px, transparent 1px),
    linear-gradient(90deg, oklch(0.2 0.02 272 / 0.032) 1px, transparent 1px);
  background-size: 58px 58px;
  mask-image: radial-gradient(74% 64% at 34% 24%, #000 14%, transparent 78%);
}
.hero .container {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(300px, 0.74fr);
  gap: clamp(2rem, 1rem + 4vw, 4.5rem);
  align-items: center;
}
.hero-content {
  max-width: 620px;
}
.hero h1 {
  margin-top: 1.5rem;
  max-width: 15ch;
  font-size: clamp(2.5rem, 1.2rem + 4.6vw, 4.3rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  font-weight: 700;
  color: var(--heading);
  text-wrap: balance;
}
.hero-copy {
  max-width: 540px;
  margin-top: 1.6rem;
  color: var(--muted-fg);
  font-size: 1.13rem;
  line-height: 1.72;
}
.hero-copy .zh {
  display: block;
  margin-top: 0.55rem;
  color: var(--muted-fg);
  font-size: 0.96rem;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 2.2rem;
}
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-top: 2.2rem;
}

/* ---------- hero phone visual ---------- */
.hero-visual {
  position: relative;
  justify-self: center;
  width: 100%;
  max-width: 344px;
}
.hero-visual .phone {
  position: relative;
  z-index: 1;
  width: 100%;
  height: auto;
  overflow: visible;
  filter:
    drop-shadow(0 28px 56px oklch(0.2 0.02 272 / 0.2))
    drop-shadow(0 12px 28px oklch(0.52 0.22 277 / 0.18));
}
.hero-visual::before {
  content: "";
  position: absolute;
  inset: -14% -22%;
  z-index: 0;
  background: radial-gradient(50% 46% at 50% 42%, var(--accent-soft), transparent 70%);
  pointer-events: none;
}
.chip {
  position: absolute;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 0.85rem;
  border-radius: var(--radius-pill);
  background: var(--glass);
  background-clip: padding-box;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px) saturate(180%);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--heading);
  white-space: nowrap;
}
.chip::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: var(--brand-grad);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
  opacity: 0.6;
}
.chip svg {
  width: 0.95rem;
  height: 0.95rem;
  color: var(--ok);
}
.chip-1 {
  top: 11%;
  left: -14%;
}
.chip-2 {
  bottom: 13%;
  right: -12%;
}
@media (prefers-reduced-motion: no-preference) {
  .chip {
    animation: floaty 5.5s var(--ease-out) infinite alternate;
  }
  .chip-2 {
    animation-delay: -2.6s;
  }
  @keyframes floaty {
    from {
      transform: translateY(-5px);
    }
    to {
      transform: translateY(5px);
    }
  }
}

/* waveform bars inside the phone svg */
@media (prefers-reduced-motion: no-preference) {
  .wave-bar {
    transform-box: fill-box;
    transform-origin: center;
    animation: wave 1.5s var(--ease-out) infinite alternate;
    will-change: transform;
  }
  @keyframes wave {
    from {
      transform: scaleY(0.45);
    }
    to {
      transform: scaleY(1);
    }
  }
}

/* ---------- capability strip ---------- */
.strip {
  border-bottom: 1px solid var(--border);
  background: var(--card);
}
.strip-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}
.strip-item {
  position: relative;
  padding: 2.3rem 2rem;
  border-right: 1px solid var(--border-soft);
  transition: background 220ms var(--ease);
}
.strip-item:last-child {
  border-right: none;
}
.strip-icon {
  display: grid;
  place-items: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 0.75rem;
  background: var(--accent-soft);
  color: var(--accent-strong);
  transition: background 240ms var(--ease), color 240ms var(--ease);
}
.strip-icon svg {
  width: 1.25rem;
  height: 1.25rem;
}
.strip-item:hover {
  background: var(--bg-tint);
}
.strip-item:hover .strip-icon {
  background: var(--brand-grad);
  color: #fff;
}
.strip-item strong {
  display: block;
  margin-top: 1.15rem;
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--heading);
}
.strip-item span {
  display: block;
  margin-top: 0.5rem;
  color: var(--muted-fg);
  font-size: 0.92rem;
  line-height: 1.65;
}

/* ---------- workflow pipeline (the Idea→Voice→Script→Video→Viral spine) ---------- */
.pipe {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0;
}
.pipe::before {
  content: "";
  position: absolute;
  top: 1.9rem;
  left: 10%;
  right: 10%;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--brand-blue), var(--brand-iris) 52%, var(--brand-violet));
  opacity: 0.85;
}
.pnode {
  position: relative;
  display: grid;
  justify-items: center;
  text-align: center;
  padding: 0 1.15rem;
}
.picon {
  position: relative;
  z-index: 1;
  width: 3.8rem;
  height: 3.8rem;
  border-radius: 1.15rem;
  display: grid;
  place-items: center;
  background: var(--card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  color: var(--accent-strong);
  transition: transform 240ms var(--ease), box-shadow 240ms var(--ease), border-color 240ms var(--ease);
}
.picon svg {
  width: 1.6rem;
  height: 1.6rem;
}
.picon.lead {
  background: var(--brand-grad);
  border-color: transparent;
  color: #fff;
  box-shadow: var(--shadow-brand);
}
.pnode:hover .picon {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--accent-line);
}
.pstep {
  margin-top: 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-variant-numeric: tabular-nums;
  color: var(--accent-strong);
}
.pnode h3 {
  margin: 0.5rem 0 0.45rem;
  font-size: 1.2rem;
  letter-spacing: -0.02em;
  font-weight: 700;
  color: var(--heading);
}
.pnode p {
  margin: 0;
  color: var(--muted-fg);
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 19ch;
}

/* ---------- product (bento scene) ---------- */
.product-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(0, 1fr);
  gap: clamp(2.5rem, 1rem + 4vw, 4.5rem);
  align-items: center;
}
.feature-list {
  display: grid;
  gap: 0.65rem;
  margin-top: 2.2rem;
}
.feature {
  display: grid;
  grid-template-columns: 2.6rem 1fr;
  gap: 1.1rem;
  align-items: start;
  padding: 1.1rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: background 200ms var(--ease), border-color 200ms var(--ease), box-shadow 200ms var(--ease);
}
.feature:hover {
  background: var(--card);
  border-color: var(--border);
  box-shadow: var(--shadow-sm);
}
.feature-mark {
  display: grid;
  place-items: center;
  width: 2.6rem;
  height: 2.6rem;
  border-radius: 0.75rem;
  background: var(--accent-soft);
  color: var(--accent-strong);
}
.feature-mark svg {
  width: 1.3rem;
  height: 1.3rem;
}
.feature strong {
  display: block;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--heading);
}
.feature p {
  margin-top: 0.35rem;
  color: var(--muted-fg);
  font-size: 0.94rem;
  line-height: 1.65;
}

/* product SVG scene */
.product-scene {
  position: relative;
  justify-self: center;
  width: 100%;
  max-width: 520px;
}
.product-scene .scene-svg {
  width: 100%;
  height: auto;
  overflow: visible;
  filter: drop-shadow(0 30px 60px oklch(0.2 0.02 272 / 0.16));
}
.product-scene::before {
  content: "";
  position: absolute;
  inset: -10% -8%;
  z-index: 0;
  background: radial-gradient(46% 50% at 60% 30%, var(--accent-soft), transparent 70%);
  pointer-events: none;
}

/* ---------- cases ---------- */
.cases {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.1rem;
}
.case {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 1.65rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--card);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: border-color 240ms var(--ease), box-shadow 240ms var(--ease), transform 240ms var(--ease);
}
.case::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 3px;
  background: var(--brand-grad);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 320ms var(--ease);
}
.case:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}
.case:hover::after {
  transform: scaleX(1);
}
.case-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  align-self: flex-start;
  padding: 0.3rem 0.65rem 0.3rem 0.5rem;
  border-radius: var(--radius-pill);
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.case-tag svg {
  width: 0.95rem;
  height: 0.95rem;
}
.case h3 {
  margin-top: 1.2rem;
  font-size: 1.32rem;
  line-height: 1.2;
  letter-spacing: -0.02em;
  font-weight: 700;
  color: var(--heading);
}
.case p {
  margin-top: 0.8rem;
  color: var(--muted-fg);
  font-size: 0.94rem;
  line-height: 1.7;
}
.case strong {
  display: block;
  margin-top: auto;
  padding-top: 1.4rem;
  color: var(--ink-soft);
  font-size: 0.8rem;
  line-height: 1.5;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* ---------- trust ---------- */
.trust-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.76fr) minmax(0, 1fr);
  gap: clamp(2.5rem, 1rem + 4vw, 4.5rem);
  align-items: start;
}
.legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-top: 1.9rem;
}
.legal-links a {
  display: inline-flex;
  align-items: center;
  height: 2.35rem;
  padding: 0 0.95rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  background: var(--card);
  color: var(--ink-soft);
  font-size: 0.84rem;
  font-weight: 600;
  box-shadow: var(--shadow-xs);
  transition: background 160ms var(--ease), color 160ms var(--ease), border-color 160ms var(--ease);
}
.legal-links a:hover {
  background: var(--accent-soft);
  border-color: var(--accent-line);
  color: var(--accent-strong);
}
.trust-panel {
  display: grid;
  gap: 0.9rem;
}
.trust-item {
  position: relative;
  padding: 1.35rem 1.5rem 1.35rem 1.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
  box-shadow: var(--shadow-xs);
  transition: box-shadow 200ms var(--ease), transform 200ms var(--ease);
}
.trust-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.4rem;
  bottom: 1.4rem;
  width: 3px;
  border-radius: 0 3px 3px 0;
  background: var(--brand-grad);
}
.trust-item:hover {
  box-shadow: var(--shadow);
  transform: translateX(2px);
}
.trust-item strong {
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--heading);
}
.trust-item p {
  margin-top: 0.5rem;
  color: var(--muted-fg);
  font-size: 0.9rem;
  line-height: 1.65;
}

/* ---------- final CTA ---------- */
.final-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.58fr);
  gap: clamp(2.5rem, 1rem + 4vw, 4.5rem);
  align-items: center;
}
.final-cta h2 {
  color: var(--heading);
}
.download-card {
  padding: 1.85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  background: var(--card);
  box-shadow: var(--shadow-brand), var(--shadow-lg);
}
.download-card p {
  color: var(--muted-fg);
  font-size: 0.9rem;
  line-height: 1.65;
}
.download-actions {
  display: grid;
  gap: 0.65rem;
  margin-top: 1.35rem;
}
.download-action {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: 3.15rem;
  padding: 0 1.15rem;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
  background: var(--card);
  color: var(--ink);
  font-size: 0.92rem;
  font-weight: 600;
  transition: background 180ms var(--ease), border-color 180ms var(--ease),
    box-shadow 180ms var(--ease), transform 180ms var(--ease);
}
.download-action:hover {
  background: var(--bg-muted);
  box-shadow: var(--shadow-sm);
  transform: translateY(-1px);
}
.download-action.primary {
  background: var(--char);
  color: #fff;
  border-color: var(--char);
}
.download-action.primary:hover {
  background: var(--char-hover);
}
.download-action .da-left {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
}
.download-action .da-left svg {
  width: 1.2rem;
  height: 1.2rem;
}
.download-action .arrow {
  opacity: 0.5;
  transition: transform 200ms var(--ease), opacity 200ms var(--ease);
}
.download-action.primary .arrow {
  opacity: 0.7;
}
.download-action:hover .arrow {
  transform: translateX(4px);
  opacity: 1;
}

/* ---------- footer ---------- */
.footer {
  padding: 2.75rem 0;
  border-top: 1px solid var(--border);
  color: var(--muted-fg);
  background: var(--card);
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  flex-wrap: wrap;
}
.footer-links {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  flex-wrap: wrap;
  font-size: 0.84rem;
  font-weight: 500;
}
.footer-links a {
  transition: color 160ms var(--ease);
}
.footer-links a:hover {
  color: var(--heading);
}

/* ---------- scroll reveal ---------- */
.reveal-ready .reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.75s var(--ease), transform 0.75s var(--ease);
  will-change: opacity, transform;
}
.reveal-ready .reveal.in {
  opacity: 1;
  transform: none;
}

/* ---------- aurora drift (gated) ---------- */
@media (prefers-reduced-motion: no-preference) {
  .hero-glow::after {
    animation: aurora 22s var(--ease-out) infinite alternate;
  }
  @keyframes aurora {
    from {
      transform: translate3d(-5%, -3%, 0) scale(1);
    }
    to {
      transform: translate3d(6%, 4%, 0) scale(1.12);
    }
  }
}

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  .hero .container {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  .hero-content {
    max-width: 640px;
  }
  .hero-visual {
    max-width: 320px;
  }
  .section-head,
  .product-layout,
  .trust-layout,
  .final-cta {
    grid-template-columns: 1fr;
    gap: 2.4rem;
  }
  .pipe {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.5rem 0;
  }
  .pipe::before {
    display: none;
  }
  .cases {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .strip-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .strip-item {
    border-right: 1px solid var(--border-soft);
    border-bottom: 1px solid var(--border-soft);
  }
  .strip-item:nth-child(2n) {
    border-right: none;
  }
  .strip-item:nth-last-child(-n + 2) {
    border-bottom: none;
  }
}

/* nav collapses earlier than the body grid — the wide EN nav needs the
   wrap + horizontal-scroll treatment before the desktop row would clip the
   lang switch / Download CTA against the container edge (~721–906px band). */
@media (max-width: 920px) {
  .nav {
    background: oklch(1 0 0 / 0.85);
    border-bottom: 1px solid var(--border);
    backdrop-filter: saturate(180%) blur(16px);
  }
  .nav-inner {
    flex-wrap: wrap;
    height: auto;
    min-height: 4.25rem;
    gap: 0.5rem;
    padding: 0.7rem 0 0.35rem;
  }
  .brand {
    flex: 0 0 auto;
  }
  .nav-cta-group {
    flex: 0 0 auto;
    margin-left: auto;
  }
  .nav-links {
    order: 3;
    width: 100%;
    overflow-x: auto;
    scrollbar-width: none;
    padding-bottom: 0.4rem;
  }
  .nav-links::-webkit-scrollbar {
    display: none;
  }
  .nav-links a {
    white-space: nowrap;
  }
}

@media (max-width: 720px) {
  .container {
    width: min(100% - 2rem, 640px);
  }
  .pipe {
    grid-template-columns: 1fr;
    gap: 1.6rem;
  }
  .pnode p {
    max-width: none;
  }
  .cases {
    grid-template-columns: 1fr;
  }
  .strip-grid {
    grid-template-columns: 1fr;
  }
  .strip-item {
    border-right: none;
    border-bottom: 1px solid var(--border-soft);
  }
  .strip-item:last-child {
    border-bottom: none;
  }
  .hero-visual::before {
    inset: -8% -8%;
  }
  .chip-1 {
    left: -1%;
  }
  .chip-2 {
    right: -1%;
  }
  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 460px) {
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .brand span {
    display: none;
  }
  .chip-1 {
    left: 0;
  }
  .chip-2 {
    right: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto;
    animation: none !important;
    transition: none !important;
  }
  .reveal-ready .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ---------- language switcher ---------- */
.lang-switch {
  position: relative;
}
.lang-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  height: 2.55rem;
  padding: 0 0.8rem;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-pill);
  background: var(--card);
  color: var(--ink);
  font-size: 0.84rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 160ms var(--ease), color 160ms var(--ease), border-color 160ms var(--ease);
}
.lang-trigger:hover {
  background: var(--bg-muted);
}
.lang-trigger .lang-globe {
  width: 1rem;
  height: 1rem;
  opacity: 0.7;
}
.lang-trigger .lang-chev {
  width: 0.7rem;
  height: 0.7rem;
  opacity: 0.6;
  transition: transform 200ms var(--ease);
}
.lang-switch[data-open="true"] .lang-chev {
  transform: rotate(180deg);
}
.lang-menu {
  position: absolute;
  top: calc(100% + 0.45rem);
  right: 0;
  z-index: 50;
  min-width: 9.5rem;
  padding: 0.35rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
  box-shadow: var(--shadow-lg);
  transform-origin: top right;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px) scale(0.97);
  pointer-events: none;
  transition: opacity 160ms var(--ease), transform 160ms var(--ease),
    visibility 0s linear 160ms;
}
.lang-switch[data-open="true"] .lang-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
  pointer-events: auto;
  transition: opacity 160ms var(--ease), transform 160ms var(--ease),
    visibility 0s;
}
.lang-menu a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  height: 2.35rem;
  padding: 0 0.65rem;
  border-radius: var(--radius-sm);
  color: var(--ink-soft);
  font-size: 0.86rem;
  font-weight: 600;
  transition: background 140ms var(--ease), color 140ms var(--ease);
}
.lang-menu a:hover {
  background: var(--bg-muted);
  color: var(--heading);
}
.lang-menu a[aria-current="true"] {
  color: var(--accent-strong);
}
.lang-menu a .lang-check {
  width: 0.9rem;
  height: 0.9rem;
  opacity: 0;
  color: var(--accent);
}
.lang-menu a[aria-current="true"] .lang-check {
  opacity: 1;
}
@media (max-width: 720px) {
  .lang-trigger {
    height: 2.3rem;
  }
}

/* ---------- CJK typesetting : professionally set Chinese ---------- */
:lang(zh) {
  letter-spacing: 0;
}
:lang(zh) h1,
:lang(zh) h2,
:lang(zh) h3 {
  letter-spacing: -0.01em;
  font-weight: 600;
}
:lang(zh) .hero-copy,
:lang(zh) .lead,
:lang(zh) p {
  font-weight: 400;
  line-height: 1.78;
}
:lang(zh) .kicker,
:lang(zh) .pstep {
  letter-spacing: 0.1em;
}