:root {
  --ink: #102a43;
  --muted: #6a7b8e;
  --line: #dbe4ee;
  --paper: #ffffff;
  --footer: #f5f8fb;
  --blue: #2458a6;
  --blue-deep: #173f7c;
  --cyan: #138bd7;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  color: var(--ink);
  background: var(--paper);
}

* { box-sizing: border-box; }
html, body { margin: 0; min-width: 320px; }
body { line-height: 1.65; }
a { color: inherit; }
.container { width: min(1160px, calc(100% - 40px)); margin-inline: auto; }

.site-header { height: 78px; display: flex; align-items: center; border-bottom: 1px solid var(--line); background: #fff; }
.header-inner { display: flex; align-items: center; }
.brand { display: inline-flex; align-items: center; gap: 12px; color: var(--ink); text-decoration: none; font-size: 19px; font-weight: 760; letter-spacing: -.02em; }
.brand-mark { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 12px; color: #fff; background: linear-gradient(145deg, #167b95, #32a8a1); box-shadow: 0 10px 28px rgba(20,124,150,.2); font-size: 22px; font-weight: 850; }

.download-hero { position: relative; overflow: hidden; min-height: 690px; display: grid; place-items: center; padding: 90px 0 92px; color: #fff; background: linear-gradient(135deg, var(--blue-deep) 0%, var(--blue) 57%, #2860b2 100%); }
.download-hero::before { content: ""; position: absolute; inset: 0; opacity: .13; background-image: linear-gradient(rgba(255,255,255,.18) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.18) 1px, transparent 1px); background-size: 58px 58px; mask-image: linear-gradient(to bottom,transparent,black 30%,transparent); }
.hero-glow { position: absolute; border-radius: 50%; filter: blur(2px); pointer-events: none; }
.hero-glow-one { width: 540px; height: 540px; top: -320px; right: -100px; background: radial-gradient(circle,rgba(52,190,211,.35),transparent 70%); }
.hero-glow-two { width: 460px; height: 460px; bottom: -330px; left: -80px; background: radial-gradient(circle,rgba(48,162,219,.28),transparent 70%); }
.hero-content { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: center; text-align: center; }
.hero-kicker { margin: 0 0 18px; color: #aee4f1; font-size: 13px; font-weight: 800; letter-spacing: .18em; }
h1 { max-width: 980px; margin: 0; font-size: clamp(44px, 5.4vw, 72px); line-height: 1.15; letter-spacing: -.04em; font-weight: 700; }
.hero-description { max-width: 930px; margin: 28px auto 0; color: rgba(255,255,255,.9); font-size: clamp(17px,2vw,22px); line-height: 1.9; }
.download-button { display: inline-flex; min-width: 250px; min-height: 68px; align-items: center; justify-content: center; margin-top: 42px; padding: 0 36px; border: 1px solid rgba(255,255,255,.2); border-radius: 8px; color: #fff; background: var(--cyan); box-shadow: 0 15px 35px rgba(4,38,90,.28); text-decoration: none; font-size: 22px; font-weight: 750; transition: transform .18s ease, background .18s ease, box-shadow .18s ease; }
.download-button:hover { transform: translateY(-2px); background: #08a0ed; box-shadow: 0 18px 42px rgba(4,38,90,.36); }
.download-button:focus-visible { outline: 3px solid #fff; outline-offset: 4px; }
.support-line { margin: 28px 0 0; color: #fff; font-size: 17px; }
.risk-note { max-width: 860px; margin: 18px auto 0; color: rgba(255,255,255,.67); font-size: 13px; }

.site-footer { padding: 64px 0 26px; background: var(--footer); }
.footer-about { max-width: 800px; }
.footer-brand { margin-bottom: 22px; }
.footer-about p { margin: 0 0 14px; color: var(--muted); font-size: 15px; }
.footer-about .legal-note { color: #8392a5; font-size: 13px; }
.footer-bottom { display: flex; justify-content: space-between; gap: 24px; margin-top: 54px; padding-top: 24px; border-top: 1px solid var(--line); color: #8392a5; font-size: 13px; }

@media (max-width: 640px) {
  .container { width: min(100% - 28px,1160px); }
  .site-header { height: 70px; }
  .brand { gap: 10px; font-size: 17px; }
  .brand-mark { width: 38px; height: 38px; font-size: 19px; }
  .download-hero { min-height: 660px; padding: 70px 0; }
  h1 { font-size: 36px; }
  .hero-description { margin-top: 22px; font-size: 16px; line-height: 1.8; }
  .download-button { width: 100%; min-height: 62px; margin-top: 34px; }
  .support-line { font-size: 14px; }
  .risk-note { font-size: 12px; }
  .site-footer { padding-top: 46px; }
  .footer-bottom { display: grid; margin-top: 38px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition-duration: .01ms !important; }
}