:root {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #20262d;
  background: #fff;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
  letter-spacing: 0;
}

* { box-sizing: border-box; }
body { margin: 0; min-width: 280px; min-height: 100svh; display: flex; flex-direction: column; }
body.wechat-only { display: block; padding: 0; }
.wechat-guide { width: min(100%, 520px); min-height: 100svh; margin: 0 auto; padding: 20px 24px 28px; display: flex; flex-direction: column; }
.wechat-guide-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; min-height: 100px; }
.wechat-guide-brand { display: flex; align-items: center; gap: 8px; margin-top: 12px; font-size: 24px; font-weight: 650; }
.wechat-guide-brand img { flex: 0 0 48px; width: 48px; height: 48px; object-fit: contain; }
.wechat-menu-cue { flex: 0 0 120px; display: flex; flex-direction: column; align-items: flex-end; gap: 6px; color: #0875ed; font-size: 12px; line-height: 1.5; }
.wechat-menu-arrow { display: block; width: 64px; height: 64px; }
.wechat-guide-intro { margin: 36px 0 28px; }
.wechat-guide h1 { font-size: 26px; line-height: 1.45; font-weight: 650; }
.wechat-guide-intro p { margin: 14px 0 0; color: #68717b; font-size: 14px; line-height: 1.7; }
.wechat-steps { margin: 0; padding: 0; list-style: none; border-top: 1px solid #e5e8ed; }
.wechat-step { display: grid; grid-template-columns: 32px minmax(0, 1fr) 24px; gap: 12px; align-items: start; min-height: 112px; padding: 24px 0; border-bottom: 1px solid #e5e8ed; }
.wechat-step-number { display: flex; align-items: center; justify-content: center; width: 32px; height: 32px; border-radius: 50%; background: #0875ed; color: #fff; font-size: 15px; font-weight: 600; }
.wechat-step-copy { min-width: 0; padding-top: 3px; }
.wechat-step-copy h2 { margin: 0; font-size: 17px; line-height: 1.5; font-weight: 600; }
.wechat-step-copy p { margin: 8px 0 0; color: #68717b; font-size: 14px; line-height: 1.7; }
.wechat-step-icon { width: 24px; height: 24px; margin-top: 4px; opacity: .55; }
.wechat-guide-note { margin: 24px 0 28px; color: #68717b; font-size: 13px; line-height: 1.7; }
.wechat-guide-domain { margin: auto 0 0; padding-top: 32px; color: #8b929b; text-align: center; font-size: 12px; line-height: 1.5; }
a { color: inherit; text-decoration: none; }
.masthead { width: min(100% - 64px, 1000px); min-height: 88px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 16px; border-bottom: 1px solid #eceef1; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 650; }
.brand img { display: block; object-fit: contain; }
.page-label { color: #7a818a; font-size: 13px; white-space: nowrap; }
main { flex: 1; width: 100%; }
.download-shell { width: min(100% - 48px, 520px); margin: 38px auto 64px; }
.intro { text-align: center; }
.app-icon { display: block; width: 136px; height: 136px; object-fit: contain; margin: 0 auto 8px; }
h1 { margin: 0; font-size: 42px; line-height: 1.3; font-weight: 650; }
.subtitle { margin: 12px 0 0; color: #68717b; font-size: 16px; line-height: 1.5; }
.release-status { display: inline-flex; align-items: center; gap: 7px; margin: 24px 0 32px; color: #7f8790; font-size: 12px; line-height: 1.5; }
.release-status > span { width: 6px; height: 6px; flex: 0 0 6px; border-radius: 50%; background: #a8afb7; }
.release-status.available { color: #23825d; }
.release-status.available > span { background: #23825d; }
.platforms { border-top: 1px solid #e5e8ed; }
.platform-row { min-height: 112px; display: flex; justify-content: space-between; align-items: center; gap: 20px; border-bottom: 1px solid #e5e8ed; }
.platform-copy { min-width: 0; }
h2 { margin: 0 0 8px; font-size: 20px; line-height: 1.25; font-weight: 600; }
.platform-copy p { margin: 0; color: #8a919a; font-size: 13px; line-height: 1.5; }
.download-button { width: 164px; min-width: 164px; height: 48px; padding: 0 14px; border: 1px solid #dce2e8; border-radius: 8px; background: #f3f5f7; color: #9199a3; display: inline-flex; align-items: center; justify-content: center; gap: 8px; font: inherit; font-size: 14px; font-weight: 550; line-height: 1.25; }
.download-button img { width: 19px; height: 19px; opacity: .4; }
.download-button:disabled { cursor: not-allowed; }
.download-button:not(:disabled) { color: white; background: #0875ed; border-color: #0875ed; cursor: pointer; }
.download-button:not(:disabled) img { opacity: 1; filter: invert(1); }
.download-button:not(:disabled):hover { background: #0067d9; }
a:focus-visible, button:focus-visible { outline: 3px solid #71b5ff; outline-offset: 4px; }
footer { width: min(100% - 64px, 1000px); margin: auto auto 0; padding: 24px 0; display: flex; justify-content: space-between; gap: 16px; border-top: 1px solid #eceef1; color: #8b929b; font-size: 12px; line-height: 1.5; }

@media (max-width: 600px) {
  .masthead { width: calc(100% - 40px); min-height: 72px; }
  .brand { font-size: 18px; gap: 6px; }
  .download-shell { width: calc(100% - 48px); margin-top: 24px; margin-bottom: 48px; }
  .app-icon { width: 120px; height: 120px; }
  h1 { font-size: 36px; }
  .subtitle { font-size: 15px; margin-top: 8px; }
  .release-status { margin-top: 20px; margin-bottom: 28px; }
  .platform-row { min-height: 104px; gap: 12px; }
  h2 { font-size: 18px; }
  .download-button { width: 144px; min-width: 144px; }
  footer { width: calc(100% - 40px); padding: 20px 0; }
}

@media (max-width: 340px) {
  .download-shell { width: calc(100% - 40px); }
  .download-button { width: 124px; min-width: 124px; }
  .page-label { font-size: 12px; }
}