:root {
  color-scheme: light;
  --blue: #1769f5;
  --blue-dark: #0a42a8;
  --ink: #101828;
  --muted: #667085;
  --line: #dce3ed;
  --mist: #f4f7fb;
  --coral: #ff5c61;
}
*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; min-height: 100vh; min-height: 100svh; display: flex; flex-direction: column; color: var(--ink); background: #fff; font-family: "PingFang SC", "Microsoft YaHei", sans-serif; font-size: 16px; line-height: 1.75; -webkit-font-smoothing: antialiased; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
button, a, summary { -webkit-tap-highlight-color: transparent; }
button, summary { cursor: pointer; }
:focus-visible { outline: 3px solid #edaa20; outline-offset: 4px; }
h1, h2, p { margin: 0; }
h1, h2 { font-family: "Songti SC", "STSong", serif; }
.shell { width: min(calc(100% - 64px), 1280px); margin-inline: auto; }
.site-header { height: 82px; border-bottom: 1px solid var(--line); flex: none; }
.header-row { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.brand { display: inline-flex; gap: 12px; align-items: center; font-size: 20px; font-weight: 800; }
.brand img { width: 46px; height: 46px; border-radius: 10px; }
.home-link { display: inline-flex; align-items: center; gap: 20px; min-height: 44px; font-size: 14px; font-weight: 600; }
.home-link:hover { color: var(--blue); }
.download-layout { display: grid; grid-template-columns: 1.1fr 1fr; flex: 1; }
.brand-story { position: relative; min-height: 740px; overflow: hidden; color: #fff; background: var(--blue); }
.brand-story::after { content: ""; position: absolute; right: 0; bottom: 0; width: 42%; height: 9px; background: var(--coral); }
.grid-pattern { position: absolute; inset: 0; background-image: linear-gradient(#ffffff14 1px, transparent 1px), linear-gradient(90deg, #ffffff14 1px, transparent 1px); background-size: 64px 64px; mask-image: linear-gradient(transparent, #000); }
.story-copy { position: relative; z-index: 2; padding: 56px 32px 0 clamp(32px, 5vw, 84px); }
.eyebrow { display: flex; align-items: center; gap: 12px; font-size: 14px; font-weight: 600; }
.eyebrow::before { content: ""; width: 30px; height: 3px; background: #fff; }
h1 { margin: 20px 0 18px; font-size: clamp(48px, 4.7vw, 72px); line-height: 1.2; font-weight: 900; }
.story-lede { color: #ffffffd9; font-size: 17px; line-height: 1.8; }
.phone-preview { position: absolute; top: 354px; right: 11%; width: 270px; height: 460px; overflow: hidden; border: 7px solid #fff; border-radius: 32px 32px 0 0; background: #fff; box-shadow: 0 24px 60px #00215e55; transform: rotate(3deg); }
.phone-preview img { width: 100%; height: auto; }
.preview-caption { position: absolute; bottom: 34px; left: clamp(32px, 5vw, 84px); color: #ffffffb3; font-size: 12px; writing-mode: vertical-rl; letter-spacing: 3px; }
.download-panel { display: flex; align-items: center; justify-content: center; padding: 58px 48px; }
.download-card { width: 100%; max-width: 390px; }
.section-kicker { margin-bottom: 16px; color: var(--blue); font-size: 14px; font-weight: 700; }
h2 { font-size: 46px; line-height: 1.35; font-weight: 800; }
.download-intro { color: var(--muted); margin-top: 18px; font-size: 15px; }
.platform-line { display: flex; align-items: center; gap: 8px; margin: 14px 0 30px; color: var(--muted); font-size: 13px; }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--blue); }
.download-actions { display: flex; flex-direction: column; gap: 12px; }
.download-button { display: flex; align-items: center; justify-content: center; width: 100%; min-height: 58px; gap: 13px; border: 1px solid transparent; border-radius: 6px; padding: 12px 22px; font-size: 17px; font-weight: 700; line-height: 1.5; transition: background .18s ease, transform .18s ease; }
.download-button:hover { transform: translateY(-1px); }
.download-button svg { width: 22px; height: 22px; flex: none; }
.button-arrow { margin-left: auto; font-size: 20px; }
.primary { background: var(--blue); color: #fff; }
.primary:hover { background: var(--blue-dark); }
.secondary { color: var(--blue); border-color: #b7cdf1; background: #fff; }
.secondary:hover { background: #f1f6ff; }
.download-hint { text-align: center; color: var(--muted); margin-top: 14px; font-size: 12px; }
.copy-link { display: block; margin: 10px auto 22px; padding: 6px 4px; min-height: 44px; color: var(--blue); border: 0; background: transparent; text-decoration: underline; text-underline-offset: 5px; font-size: 13px; }
.install-help { border-top: 1px solid var(--line); margin-top: 24px; color: var(--muted); font-size: 14px; }
summary { min-height: 58px; display: flex; justify-content: space-between; align-items: center; list-style: none; gap: 10px; color: var(--ink); }
summary::-webkit-details-marker { display: none; }
summary span { font-size: 22px; color: var(--blue); }
details[open] summary span { transform: rotate(45deg); }
.install-help ol { margin: 0 0 20px; padding-left: 22px; }
.install-help li { margin-bottom: 8px; }
.wechat-notice { padding: 16px 18px; margin-bottom: 22px; border-left: 3px solid var(--blue); background: #f1f6ff; font-size: 14px; }
.wechat-notice strong { color: var(--blue-dark); }
.wechat-notice p { margin-top: 4px; color: var(--muted); }
.no-script-note { margin-top: 16px; font-size: 14px; color: var(--muted); }
.site-footer { padding: 22px 0 max(22px, env(safe-area-inset-bottom)); color: var(--muted); background: var(--mist); font-size: 12px; flex: none; }
.footer-row, .footer-identity { display: flex; align-items: center; justify-content: space-between; gap: 12px 22px; flex-wrap: wrap; }
.toast { position: fixed; z-index: 60; bottom: max(28px, env(safe-area-inset-bottom)); left: 50%; transform: translateX(-50%); width: max-content; max-width: calc(100% - 40px); padding: 14px 22px; color: #fff; background: var(--ink); border-radius: 6px; box-shadow: 0 8px 30px #10182822; font-size: 14px; }
.toast:empty { display: none; }
dialog { max-height: calc(100svh - 40px); overflow: auto; width: min(420px, calc(100% - 40px)); margin: auto; padding: 32px; border: 1px solid var(--line); border-radius: 8px; color: var(--ink); background: #fff; box-shadow: 0 24px 90px #10182833; }
dialog::backdrop { background: #041126aa; }
dialog h2 { font-size: 29px; }
dialog ol, dialog p { color: var(--muted); font-size: 15px; }
dialog ol { padding-left: 22px; margin: 20px 0 26px; }
dialog li { margin-bottom: 12px; }
dialog p { margin: 16px 0; }
dialog .dialog-kicker { color: var(--blue); margin: 0 0 8px; font-size: 13px; font-weight: 700; }
#manual-link { width: 100%; min-height: 48px; padding: 10px; margin-bottom: 24px; border: 1px solid var(--line); border-radius: 4px; background: var(--mist); font-size: 14px; }
@media (min-width: 1600px) { .brand-story { min-height: 800px; }.phone-preview { width: 310px; top: 350px; height: 550px; right: 16%; }.story-copy { padding-top: 70px; } }
@media (max-width: 980px) and (min-width: 761px) { .download-panel { padding: 44px 30px; } h2 { font-size: 38px; }.phone-preview { right: 6%; width: 248px; }.story-copy { padding-left: 30px; }.story-lede { font-size: 15px; } }
@media (max-width: 760px) {
  .shell { width: calc(100% - 40px); }
  .site-header { height: 70px; }
  .brand { gap: 10px; font-size: 18px; }
  .brand img { width: 40px; height: 40px; }
  .home-link { font-size: 13px; gap: 12px; }
  .download-layout { grid-template-columns: minmax(0, 1fr); }
  .brand-story { min-height: 280px; }
  .story-copy { width: 72%; padding: 32px 0 32px 24px; }
  .eyebrow { font-size: 11px; gap: 8px; }
  .eyebrow::before { width: 16px; height: 2px; }
  h1 { font-size: 39px; margin: 16px 0 12px; }
  .story-lede { font-size: 12px; }
  .phone-preview { top: 82px; right: -18px; width: 150px; height: 300px; border-width: 4px; border-radius: 20px 20px 0 0; transform: rotate(8deg); }
  .preview-caption { display: none; }
  .download-panel { padding: 34px 24px 28px; }
  .download-card { max-width: 460px; }
  .section-kicker { font-size: 12px; margin-bottom: 12px; }
  h2 { font-size: 34px; }
  .download-intro { margin-top: 12px; font-size: 14px; }
  .platform-line { margin: 12px 0 22px; }
  .download-button { min-height: 56px; font-size: 16px; }
  .footer-row, .footer-identity { align-items: flex-start; flex-direction: column; gap: 5px; }
  .site-footer { padding-top: 20px; }
}
@media (max-width: 350px) { .story-copy { padding-left: 20px; width: 78%; }h1 { font-size: 35px; }.phone-preview { right: -43px; }.download-panel { padding-inline: 20px; }h2 { font-size: 30px; }.home-link { gap: 6px; }.brand { font-size: 16px; } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; } }