:root {
  color-scheme: light;
  --ink: #202429;
  --muted: #687079;
  --line: #dfe6e4;
  --paper: #f4f7f6;
  --card: rgba(255, 255, 255, 0.88);
  --teal: #2d9c87;
  --teal-dark: #207866;
  --sand: #c7b996;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 84% 12%, rgba(45, 156, 135, 0.13), transparent 28rem),
    linear-gradient(145deg, #f8faf9 0%, var(--paper) 62%, #edf3f1 100%);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Microsoft YaHei", sans-serif;
}

main { width: min(1160px, calc(100% - 40px)); margin: 0 auto; }

.site-header {
  min-height: 92px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}

.brand { display: flex; align-items: center; gap: 13px; color: inherit; text-decoration: none; }
.brand img { width: 49px; height: 49px; border-radius: 14px; box-shadow: 0 8px 22px rgba(47, 57, 55, 0.13); }
.brand span { display: grid; gap: 2px; }
.brand strong { font-size: 21px; letter-spacing: 0.01em; }
.brand small { color: var(--muted); font-size: 13px; }
.privacy-badge { padding: 8px 12px; border: 1px solid #bcded6; border-radius: 999px; color: var(--teal-dark); background: #eaf7f3; font-size: 13px; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(320px, .75fr);
  gap: 72px;
  align-items: center;
  min-height: 600px;
  padding: 70px 0;
}

.eyebrow { margin: 0 0 14px; color: var(--teal-dark); font-size: 12px; font-weight: 750; letter-spacing: .18em; }
h1 { margin: 0; max-width: 700px; font-size: clamp(48px, 6vw, 76px); line-height: 1.06; letter-spacing: -.045em; }
.intro { max-width: 650px; margin: 26px 0 0; color: var(--muted); font-size: 18px; line-height: 1.8; }
.actions { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; margin-top: 34px; }
.download-button { display: inline-flex; align-items: center; min-height: 54px; padding: 0 24px; border-radius: 14px; color: white; background: var(--teal); box-shadow: 0 14px 30px rgba(45, 156, 135, .24); text-decoration: none; font-weight: 700; transition: transform .18s ease, background .18s ease; }
.download-button:hover { transform: translateY(-2px); background: var(--teal-dark); }
.platform { color: var(--muted); font-size: 13px; }

.release-card { padding: 30px; border: 1px solid rgba(210, 221, 218, .9); border-radius: 28px; background: var(--card); box-shadow: 0 28px 70px rgba(48, 63, 59, .12); backdrop-filter: blur(18px); }
.app-icon img { width: 78px; height: 78px; border-radius: 22px; box-shadow: 0 14px 30px rgba(52, 57, 55, .14); }
.version { display: inline-block; margin-top: 25px; color: var(--teal-dark); font-size: 13px; font-weight: 700; }
.release-card h2 { margin: 8px 0 10px; font-size: 28px; letter-spacing: -.02em; }
.release-card p { color: var(--muted); line-height: 1.7; }
dl { margin: 25px 0 0; padding-top: 20px; border-top: 1px solid var(--line); }
dl div { display: flex; justify-content: space-between; gap: 18px; padding: 8px 0; font-size: 14px; }
dt { color: var(--muted); } dd { margin: 0; font-weight: 650; }

.steps, .security-note { margin: 20px 0 70px; padding: 42px; border: 1px solid var(--line); border-radius: 28px; background: rgba(255, 255, 255, .66); }
.section-heading h2, .security-note h2 { margin: 0; font-size: 34px; letter-spacing: -.025em; }
.steps ol { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin: 32px 0 0; padding: 0; list-style: none; }
.steps li { display: flex; gap: 16px; padding: 22px; border-radius: 18px; background: white; }
.steps li > span { flex: 0 0 34px; height: 34px; display: grid; place-items: center; border-radius: 50%; color: var(--teal-dark); background: #e9f6f2; font-weight: 750; }
.steps strong { font-size: 16px; } .steps p { margin: 7px 0 0; color: var(--muted); line-height: 1.6; font-size: 14px; }

.security-note { display: grid; grid-template-columns: .65fr 1.35fr; align-items: center; gap: 34px; }
.security-note p:not(.eyebrow) { color: var(--muted); line-height: 1.7; }
.help-card { padding: 22px; border-radius: 16px; background: #25302e; color: #f1f8f6; }
.help-card strong { font-size: 16px; }
.help-card p { margin: 8px 0 0; color: #c8d6d2 !important; }

footer { display: flex; justify-content: space-between; gap: 20px; padding: 30px 0 50px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }

@media (max-width: 820px) {
  main { width: min(100% - 28px, 680px); }
  .hero { grid-template-columns: 1fr; gap: 42px; min-height: auto; padding: 56px 0; }
  h1 { font-size: clamp(42px, 13vw, 64px); }
  .steps, .security-note { padding: 26px; }
  .steps ol, .security-note { grid-template-columns: 1fr; }
  footer { flex-direction: column; }
}

@media (max-width: 480px) {
  .site-header { min-height: 78px; }
  .privacy-badge { display: none; }
  .hero { padding-top: 42px; }
  .release-card { padding: 24px; }
  .download-button { width: 100%; justify-content: center; }
}