:root {
  --bg: #fbfbfd;
  --bg-soft: #f2f2f5;
  --surface: #ffffff;
  --text: #1d1d1f;
  --text-soft: #6e6e73;
  --line: rgba(0,0,0,.10);
  --accent: #f5b400;
  --accent-ink: #6b4e00;
  --shadow: 0 16px 50px rgba(0,0,0,.10);
  --radius: 18px;
  --maxw: 1080px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --bg-soft: #0d0d0f;
    --surface: #161618;
    --text: #f5f5f7;
    --text-soft: #a1a1a6;
    --line: rgba(255,255,255,.12);
    --shadow: 0 16px 50px rgba(0,0,0,.55);
  }
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

a { color: inherit; text-decoration: none; }

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

/* i18n visibility — handled by JS swapping text; no CSS needed */

/* ---------- nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 17px; }
.brand-mark { width: 22px; height: 22px; flex: none; display: block; }
.nav-links { display: flex; align-items: center; gap: 26px; font-size: 15px; }
.nav-links a { color: var(--text-soft); transition: color .15s; }
.nav-links a:hover { color: var(--text); }
.lang-toggle {
  font: inherit; font-size: 14px; cursor: pointer;
  background: var(--bg-soft); color: var(--text);
  border: 1px solid var(--line); border-radius: 999px;
  padding: 5px 14px; transition: background .15s;
}
.lang-toggle:hover { background: var(--surface); }

/* ---------- hero ---------- */
.hero { padding: 84px 0 40px; text-align: center; }
.hero-icon {
  width: clamp(88px, 12vw, 120px); height: auto;
  margin: 0 auto 26px;
  filter: drop-shadow(0 14px 30px rgba(0,0,0,.28));
}
.eyebrow {
  font-size: 14px; font-weight: 600; letter-spacing: .04em;
  color: var(--accent-ink); text-transform: uppercase;
}
@media (prefers-color-scheme: dark) { .eyebrow { color: var(--accent); } }
.hero h1 {
  font-size: clamp(36px, 6vw, 64px);
  line-height: 1.08; font-weight: 700; letter-spacing: -.02em;
  margin: 16px auto 0; max-width: 14ch;
}
.lede {
  font-size: clamp(17px, 2.2vw, 21px);
  color: var(--text-soft); margin: 22px auto 0; max-width: 60ch;
}
.cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin: 34px 0 14px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 16px; font-weight: 600;
  padding: 13px 26px; border-radius: 999px;
  transition: transform .12s ease, box-shadow .12s ease, background .15s;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: linear-gradient(180deg, #ffd14d, var(--accent));
  color: var(--accent-ink);
  box-shadow: 0 8px 22px rgba(245,180,0,.35);
}
.btn-primary:hover { box-shadow: 0 10px 28px rgba(245,180,0,.5); }
.btn-ghost { background: var(--bg-soft); color: var(--text); border: 1px solid var(--line); }
.btn-ghost:hover { background: var(--surface); }
.dl-version { font-weight: 500; opacity: .7; font-size: 14px; }
.req { font-size: 14px; color: var(--text-soft); }

.hero-shot {
  margin: 56px auto 0; max-width: 960px;
  border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow); border: 1px solid var(--line);
}

/* ---------- features ---------- */
.features { padding: 80px 24px; display: flex; flex-direction: column; gap: 96px; }
.feature {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 56px; align-items: center;
}
.feature.reverse .feature-text { order: 2; }
.feature h2 {
  font-size: clamp(26px, 3.4vw, 38px);
  line-height: 1.15; letter-spacing: -.02em; font-weight: 700;
}
.feature p { margin-top: 16px; font-size: 17px; color: var(--text-soft); }
.feature ul { margin-top: 18px; padding-left: 0; list-style: none; display: grid; gap: 10px; }
.feature li { font-size: 15.5px; color: var(--text-soft); padding-left: 22px; position: relative; }
.feature li::before {
  content: ""; position: absolute; left: 0; top: 9px;
  width: 7px; height: 7px; border-radius: 50%; background: var(--accent);
}
.feature li b { color: var(--text); }
.feature-media {
  border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow); border: 1px solid var(--line);
  background: var(--surface);
}
.feature-media img { width: 100%; }

/* ---------- grid cards ---------- */
.grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}
.card {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 26px;
}
.card h3 { font-size: 18px; font-weight: 650; }
.card p { margin-top: 10px; font-size: 15px; color: var(--text-soft); }

/* ---------- download ---------- */
.download {
  text-align: center; padding: 96px 24px;
  background: var(--bg-soft); border-top: 1px solid var(--line);
}
.download h2 { font-size: clamp(28px, 4vw, 42px); font-weight: 700; letter-spacing: -.02em; }
.download .body, .download > .wrap > p:first-of-type { }
.download p { color: var(--text-soft); max-width: 52ch; margin: 16px auto 0; font-size: 17px; }
.download .cta { margin-top: 30px; }
.download .req { margin-top: 6px; }

/* ---------- footer ---------- */
.footer { border-top: 1px solid var(--line); padding: 34px 0; font-size: 14px; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 16px; }
.footer-inner > div { display: flex; align-items: center; gap: 10px; }
.footer-name { font-weight: 600; }
.footer-copy { color: var(--text-soft); }
.footer-links { display: flex; gap: 22px; }
.footer-links a { color: var(--text-soft); transition: color .15s; }
.footer-links a:hover { color: var(--text); }

/* ---------- responsive ---------- */
@media (max-width: 820px) {
  .nav-links { gap: 16px; font-size: 14px; }
  .feature { grid-template-columns: 1fr; gap: 28px; }
  .feature.reverse .feature-text { order: 0; }
  .grid { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 24px; }
  .hero-shot { margin-top: 40px; }
  .features { padding: 56px 20px; gap: 64px; }
}
@media (max-width: 520px) {
  .nav-links a:not(:last-of-type) { display: none; }
}