:root {
  --accent: #6750A4;
  --accent-soft: #EDE7F6;
  --accent-ink: #4F378B;
  --bg: #FFFBFE;
  --surface: #FFFFFF;
  --text: #1C1B1F;
  --text-muted: #5C5C5F;
  --border: rgba(28, 27, 31, 0.10);
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 10px;
  --maxw: 1080px;
  --font: "Segoe UI", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

/* ---- bilingual switch ---- */
.t-en { display: none; }
html[data-lang="en"] .t-zh { display: none; }
html[data-lang="en"] .t-en { display: revert; }

/* ---- nav ---- */
.nav {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px clamp(16px, 4vw, 40px);
  background: rgba(255, 251, 254, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 8px; font-weight: 600; font-size: 16px; }
.nav-links { display: flex; gap: 20px; margin-left: auto; font-size: 14px; color: var(--text-muted); }
.nav-links a:hover { color: var(--accent); }
.lang-toggle {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--accent);
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}
.lang-toggle:hover { background: var(--accent-soft); }

/* ---- hero ---- */
.hero {
  padding: clamp(48px, 9vw, 96px) clamp(16px, 4vw, 40px) clamp(32px, 6vw, 64px);
  background: radial-gradient(1200px 420px at 50% -10%, var(--accent-soft), transparent 70%);
}
.hero-inner { max-width: var(--maxw); margin: 0 auto; text-align: center; }
.badge {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--accent-ink);
  font-size: 13px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 20px;
}
.hero h1 {
  font-size: clamp(28px, 5vw, 46px);
  line-height: 1.2;
  margin: 0 0 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.subtitle {
  max-width: 640px;
  margin: 0 auto 28px;
  color: var(--text-muted);
  font-size: clamp(15px, 2vw, 17px);
}
.cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .08s ease, background .15s ease;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-ink); }
.btn-ghost { background: transparent; color: var(--accent); border: 1px solid var(--accent); }
.btn-ghost:hover { background: var(--accent-soft); }

/* ---- sections ---- */
.section { max-width: var(--maxw); margin: 0 auto; padding: clamp(40px, 7vw, 72px) clamp(16px, 4vw, 40px); }
.section-head { text-align: center; margin-bottom: 36px; }
.section-head h2 { font-size: clamp(24px, 4vw, 34px); margin: 0 0 8px; font-weight: 700; }
.section-head p { color: var(--text-muted); margin: 0; }

/* ---- feature grid ---- */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(248px, 1fr)); gap: 18px; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: box-shadow .15s ease, transform .15s ease;
}
.card:hover { box-shadow: 0 8px 24px rgba(103, 80, 164, 0.12); transform: translateY(-2px); }
.card-icon {
  width: 44px; height: 44px;
  display: flex; align-items: center; justify-content: center;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 12px;
  font-size: 22px;
  margin-bottom: 14px;
}
.card h3 { margin: 0 0 8px; font-size: 17px; font-weight: 600; }
.card p { margin: 0; color: var(--text-muted); font-size: 14px; }

/* ---- gallery ---- */
.gallery { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px; }
.gallery img {
  width: 100%;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--surface);
  aspect-ratio: 9 / 16;
  object-fit: cover;
}

/* ---- download ---- */
.download { background: var(--accent-soft); }
.download-inner { max-width: 720px; margin: 0 auto; text-align: center; }
.download h2 { font-size: clamp(24px, 4vw, 32px); margin: 0 0 8px; font-weight: 700; }
.download p { color: var(--text-muted); margin: 0 0 28px; }
.download-row { display: flex; gap: 28px; align-items: center; justify-content: center; flex-wrap: wrap; }
.qr-box {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 16px;
  display: flex; flex-direction: column; align-items: center; gap: 8px;
  box-shadow: 0 6px 20px rgba(103, 80, 164, 0.15);
}
.qr-cap { font-size: 13px; color: var(--text-muted); }
.store-links { display: flex; flex-direction: column; gap: 12px; }
.store-btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 180px;
  padding: 12px 20px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--border);
  font-weight: 600;
  color: var(--accent-ink);
}
.store-btn:hover { background: var(--accent-soft); }

/* ---- footer ---- */
.footer { border-top: 1px solid var(--border); padding: 28px clamp(16px, 4vw, 40px); }
.footer-inner {
  max-width: var(--maxw); margin: 0 auto;
  display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  font-size: 14px; color: var(--text-muted);
}
.footer-brand { font-weight: 600; color: var(--text); }
.footer-links { display: flex; gap: 18px; }
.footer-links a:hover { color: var(--accent); }
.footer-copy { margin-left: auto; }

@media (max-width: 560px) {
  .nav-links { display: none; }
  .footer-copy { margin-left: 0; width: 100%; }
}