:root {
  --blue: #2f6feb;
  --blue-dark: #1f55c5;
  --blue-soft: #edf4ff;
  --ink: #172033;
  --muted: #5f6b7c;
  --line: #dfe5ec;
  --page: #ffffff;
  --soft: #f6f8fb;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; overflow-x: hidden; }
body {
  margin: 0;
  overflow-x: hidden;
  background: var(--page);
  color: var(--ink);
  font-family: "Microsoft YaHei UI", "PingFang SC", system-ui, sans-serif;
  letter-spacing: 0;
}
a { color: inherit; text-decoration: none; }

.site-header {
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 max(24px, calc((100% - 1120px) / 2));
  background: rgba(255, 255, 255, .96);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 20;
}
.brand, .footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.brand img, .footer-brand img, .download-section img { border-radius: 8px; }
.site-header nav { display: flex; align-items: center; gap: 28px; font-size: 14px; }
.site-header nav > a:hover { color: var(--blue); }
.header-download {
  padding: 9px 15px;
  color: #fff !important;
  background: var(--blue);
  border-radius: 5px;
}
.header-download:hover { background: var(--blue-dark); }

.hero { background: var(--soft); border-bottom: 1px solid var(--line); }
.hero-inner {
  max-width: 1120px;
  min-height: 650px;
  margin: auto;
  padding: 70px 24px 0;
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: 80px;
  align-items: center;
  overflow: hidden;
}
.kicker { margin: 0 0 14px; color: var(--blue); font-size: 13px; font-weight: 700; }
.hero h1 { margin: 0; font-size: 64px; line-height: 1.15; font-weight: 800; }
.hero-text { max-width: 520px; margin: 24px 0 0; color: var(--muted); font-size: 18px; line-height: 1.8; }
.hero-actions { display: flex; align-items: center; gap: 24px; margin-top: 32px; }
.button-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 46px;
  padding: 0 20px;
  color: #fff;
  background: var(--blue);
  border-radius: 5px;
  font-size: 15px;
  font-weight: 700;
}
.button-primary:hover { background: var(--blue-dark); }
.android-mark { font-size: 18px; }
.text-link { color: var(--blue-dark); font-size: 14px; }
.text-link:hover { text-decoration: underline; text-underline-offset: 4px; }
.download-note { margin: 14px 0 0; color: #7a8595; font-size: 12px; }
.hero-screens { height: 580px; position: relative; align-self: end; }
.hero-screens img {
  position: absolute;
  width: 270px;
  border: 1px solid #cad3df;
  border-radius: 29px;
  box-shadow: 0 20px 44px rgba(28, 45, 75, .14);
}
.hero-screens img:first-child { left: 10px; top: 80px; }
.hero-screens img:last-child { right: 0; top: 15px; }

.feature-section { max-width: 1120px; margin: auto; padding: 96px 24px; }
.section-title { max-width: 640px; margin-bottom: 48px; }
.section-title h2, .detail-copy h2, .privacy-section h2, .download-section h2 {
  margin: 0;
  font-size: 36px;
  line-height: 1.35;
}
.section-title > p:last-child { margin: 16px 0 0; color: var(--muted); line-height: 1.8; }
.feature-list { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--line); }
.feature-list article {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 20px;
  padding: 30px 34px 30px 0;
  border-bottom: 1px solid var(--line);
}
.feature-list article:nth-child(odd) { border-right: 1px solid var(--line); }
.feature-list article:nth-child(even) { padding-left: 34px; }
.feature-icon {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  background: var(--blue-soft);
  color: var(--blue-dark);
  border-radius: 7px;
  font-size: 14px;
  font-weight: 800;
}
.feature-list h3 { margin: 0 0 9px; font-size: 19px; }
.feature-list p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }

.detail-section {
  max-width: 1120px;
  margin: 0 auto 96px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--soft);
  border: 1px solid var(--line);
}
.detail-image { min-height: 610px; padding: 55px 0 0; display: flex; justify-content: center; overflow: hidden; }
.detail-image img { width: 285px; border: 1px solid #ccd5e1; border-radius: 29px; box-shadow: 0 18px 40px rgba(28,45,75,.13); }
.detail-copy { padding: 72px 64px; background: #fff; border-left: 1px solid var(--line); }
.detail-copy ol { margin: 40px 0 0; padding: 0; list-style: none; }
.detail-copy li { display: grid; grid-template-columns: 32px 1fr; gap: 16px; padding: 20px 0; border-top: 1px solid var(--line); }
.detail-copy li > span { width: 28px; height: 28px; display: grid; place-items: center; color: var(--blue); border: 1px solid #b9cae8; border-radius: 50%; font-size: 12px; }
.detail-copy strong { font-size: 15px; }
.detail-copy li p { margin: 6px 0 0; color: var(--muted); font-size: 14px; line-height: 1.7; }

.privacy-section {
  max-width: 1120px;
  margin: 0 auto 96px;
  padding: 52px 56px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  background: #f0f5fc;
  border: 1px solid #d5dfed;
}
.privacy-section > div:last-child { padding-top: 28px; }
.privacy-section p { margin: 0; color: var(--muted); line-height: 1.85; }
.privacy-section a { display: inline-block; margin-top: 20px; color: var(--blue-dark); font-weight: 700; }

.download-section {
  max-width: 1120px;
  margin: 0 auto 96px;
  padding: 36px 42px;
  display: grid;
  grid-template-columns: 72px 1fr auto;
  align-items: center;
  gap: 24px;
  border: 1px solid var(--line);
}
.download-section h2 { font-size: 25px; }
.download-section p { margin: 6px 0 0; color: var(--muted); font-size: 14px; }

footer {
  max-width: 1120px;
  margin: auto;
  padding: 34px 0 46px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  color: var(--muted);
  border-top: 1px solid var(--line);
  font-size: 13px;
}
footer p { margin: 6px 0; text-align: right; }
.footer-links { display: flex; gap: 22px; }
footer small { text-align: right; }
.footer-links a:hover { color: var(--blue); }

@media (max-width: 900px) {
  .site-header { padding: 0 18px; }
  .site-header nav { gap: 16px; }
  .site-header nav > a:not(.header-download) { display: none; }
  .hero-inner { min-height: auto; grid-template-columns: 1fr; gap: 35px; padding-top: 55px; }
  .hero-screens { height: 510px; width: min(560px, 100%); margin: auto; }
  .hero-screens img { width: 235px; }
  .hero-screens img:first-child { left: 8%; }
  .hero-screens img:last-child { right: 8%; }
  .detail-section { margin-left: 20px; margin-right: 20px; }
  .detail-copy { padding: 55px 38px; }
  .privacy-section, .download-section { margin-left: 20px; margin-right: 20px; }
  footer { margin: 0 20px; }
}

@media (max-width: 620px) {
  .hero-inner { padding: 42px 22px 0; }
  .hero h1 { font-size: 46px; }
  .hero-text { font-size: 16px; }
  .hero-actions { align-items: flex-start; flex-direction: column; gap: 18px; }
  .hero-screens { height: 430px; }
  .hero-screens img { width: 205px; }
  .hero-screens img:first-child { left: -28px; top: 70px; }
  .hero-screens img:last-child { right: -18px; top: 10px; }
  .feature-section { padding-top: 72px; padding-bottom: 72px; }
  .section-title h2, .detail-copy h2, .privacy-section h2 { font-size: 29px; }
  .feature-list { grid-template-columns: 1fr; }
  .feature-list article, .feature-list article:nth-child(even) { padding: 25px 0; border-right: 0; }
  .detail-section { grid-template-columns: 1fr; margin-bottom: 72px; }
  .detail-image { min-height: 500px; padding-top: 40px; }
  .detail-image img { width: 240px; }
  .detail-copy { padding: 44px 26px; border-left: 0; border-top: 1px solid var(--line); }
  .privacy-section { grid-template-columns: 1fr; gap: 15px; margin-bottom: 72px; padding: 36px 26px; }
  .privacy-section > div:last-child { padding-top: 0; }
  .download-section { grid-template-columns: 56px 1fr; padding: 28px 24px; }
  .download-section img { width: 56px; height: 56px; }
  .download-section .button-primary { grid-column: 1 / -1; width: 100%; margin-top: 8px; }
  footer { grid-template-columns: 1fr; }
  footer p, footer small { text-align: left; }
}