:root {
  --brand: #5566fc;
  --brand-dark: #3d4de0;
  --brand-soft: #eef0ff;
  --text: #1a1d26;
  --muted: #5b6170;
  --line: #e8eaf0;
  --bg: #f6f7fb;
  --card: #ffffff;
  --radius: 16px;
  --shadow: 0 12px 40px rgba(26, 29, 38, 0.08);
  --max: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
img { max-width: 100%; display: block; }
.container { width: min(100% - 32px, var(--max)); margin: 0 auto; }

.topbar {
  background: #101322;
  color: rgba(255, 255, 255, 0.82);
  font-size: 13px;
}
.topbar-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
}
.topbar a { color: rgba(255, 255, 255, 0.9); }
.topbar a:hover { color: #fff; }

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 700;
  font-size: 15px;
  line-height: 1.3;
  max-width: min(520px, 48vw);
}
.brand img { width: 40px; height: 40px; border-radius: 10px; }
.nav-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 18px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a { color: var(--muted); font-weight: 500; }
.nav-links a:hover { color: var(--brand); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  border-radius: 999px;
  padding: 12px 22px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: 0.2s ease;
}
.btn-primary {
  background: var(--brand);
  color: #fff;
}
.btn-primary:hover {
  background: var(--brand-dark);
  color: #fff;
}
.btn-ghost {
  background: #fff;
  color: var(--text);
  border: 1px solid var(--line);
}
.btn-ghost:hover {
  border-color: var(--brand);
  color: var(--brand);
}
.btn-lg { padding: 14px 28px; font-size: 16px; }

.hero {
  padding: 72px 0 56px;
  background:
    radial-gradient(circle at 12% 20%, rgba(85, 102, 252, 0.18), transparent 40%),
    radial-gradient(circle at 88% 10%, rgba(85, 102, 252, 0.12), transparent 36%),
    linear-gradient(180deg, #fff 0%, var(--bg) 100%);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 40px;
  align-items: center;
}
.eyebrow {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--brand-soft);
  color: var(--brand);
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 16px;
}
.hero h1 {
  margin: 0 0 16px;
  font-size: clamp(32px, 5vw, 48px);
  line-height: 1.2;
  letter-spacing: -0.02em;
}
.hero h1 span { color: var(--brand); }
.hero-desc {
  margin: 0 0 28px;
  color: var(--muted);
  font-size: 17px;
  max-width: 36em;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow);
  padding: 28px;
  text-align: center;
}
.hero-card img {
  width: 148px;
  height: 148px;
  margin: 0 auto 16px;
  border-radius: 28px;
}
.hero-card h3 { margin: 0 0 8px; }
.hero-card p { margin: 0; color: var(--muted); }

.section { padding: 72px 0; }
.section.alt { background: #fff; }
.section-head { text-align: center; margin-bottom: 40px; }
.section-head .label {
  color: var(--brand);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 10px;
}
.section-head h2 {
  margin: 0 0 12px;
  font-size: clamp(26px, 3.5vw, 36px);
}
.section-head p {
  margin: 0 auto;
  max-width: 40em;
  color: var(--muted);
}

.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 28px;
  align-items: stretch;
}
.about-copy,
.about-panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
}
.about-copy h3 { margin-top: 0; font-size: 24px; }
.about-copy p { color: var(--muted); }
.about-panel {
  background: linear-gradient(160deg, #5566fc, #7b5cff);
  color: #fff;
  border: none;
}
.about-panel h4 { margin: 0 0 12px; font-size: 20px; }
.about-panel ul {
  margin: 0;
  padding-left: 18px;
}
.about-panel li { margin-bottom: 10px; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.feature-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
}
.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: var(--brand-soft);
  color: var(--brand);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
}
.feature-card h3 { margin: 0 0 10px; font-size: 18px; }
.feature-card p { margin: 0; color: var(--muted); font-size: 14px; }

.download-box {
  text-align: center;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: 48px 24px;
  box-shadow: var(--shadow);
}
.download-box img {
  width: 96px;
  height: 96px;
  margin: 0 auto 18px;
  border-radius: 22px;
}
.download-box p { color: var(--muted); margin: 0 0 24px; }

.contact-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.contact-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  text-align: center;
  box-shadow: var(--shadow);
}
.contact-card strong {
  display: block;
  margin-bottom: 8px;
  font-size: 15px;
}
.contact-card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.footer {
  background: #101322;
  color: rgba(255, 255, 255, 0.78);
  padding: 48px 0 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}
.footer .brand { color: #fff; margin-bottom: 12px; }
.footer h4 {
  margin: 0 0 14px;
  color: #fff;
  font-size: 15px;
}
.footer ul { list-style: none; margin: 0; padding: 0; }
.footer li { margin-bottom: 8px; }
.footer a { color: rgba(255, 255, 255, 0.78); }
.footer a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 18px;
  text-align: center;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
}
.footer-bottom a { color: rgba(255, 255, 255, 0.7); }

.legal-wrap {
  max-width: 760px;
  margin: 40px auto 64px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 28px 22px 36px;
  box-shadow: var(--shadow);
}
.legal-wrap h1 { margin: 0 0 8px; font-size: 24px; }
.legal-wrap .meta {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}
.legal-wrap h2 { font-size: 17px; margin: 22px 0 10px; }
.legal-wrap p { color: var(--muted); font-size: 14px; margin: 0 0 10px; }
.legal-wrap .legal-footer {
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--muted);
}

@media (max-width: 900px) {
  .hero-grid,
  .about-grid,
  .feature-grid,
  .contact-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .nav { flex-direction: column; align-items: flex-start; }
}