:root {
  color-scheme: light;
  --ink: #202522;
  --muted: #7b837e;
  --line: #dfe5e1;
  --surface: #ffffff;
  --page: #f4f7f5;
  --brand: #43a174;
  --brand-dark: #287b55;
  --warm: #ffbe55;
}

* { box-sizing: border-box; }

html { background: var(--page); }

body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  background: var(--page);
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  letter-spacing: 0;
}

button { font: inherit; }

.page-shell {
  width: min(100%, 480px);
  min-height: 100vh;
  margin: 0 auto;
  padding: 22px 20px 24px;
}

.app-intro {
  display: grid;
  grid-template-columns: 82px minmax(0, 1fr);
  align-items: center;
  gap: 18px;
  min-height: 0;
  padding: 24px 0 30px;
  border-bottom: 1px solid var(--line);
}

.app-icon {
  width: 82px;
  height: 82px;
  border-radius: 18px;
  object-fit: cover;
  background: var(--surface);
  box-shadow: 0 12px 30px rgba(22, 43, 31, .12);
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--brand-dark);
  font-size: 14px;
  font-weight: 700;
}

h1, h2, p { margin-top: 0; }

h1 {
  margin-bottom: 10px;
  font-size: 28px;
  line-height: 1.15;
  font-weight: 750;
}

.subtitle {
  margin-bottom: 12px;
  color: #4d5751;
  font-size: 15px;
  line-height: 1.6;
}

.description {
  grid-column: 1 / -1;
  max-width: 520px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.75;
}

.download-actions {
  display: grid;
  grid-column: 1 / -1;
  width: min(100%, 248px);
  margin-top: 4px;
  justify-self: center;
}

.download-button {
  display: flex;
  min-height: 62px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: 8px;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  transition: transform .16s ease, background-color .16s ease, border-color .16s ease;
}

.download-button:hover { transform: translateY(-1px); }
.download-button:active { transform: translateY(0); }
.download-button[disabled] { cursor: not-allowed; opacity: .45; transform: none; }
.download-button span { font-size: 16px; font-weight: 700; }
.download-button small { font-size: 12px; }
.download-button.primary { color: white; background: var(--brand); }
.download-button.primary:hover { background: var(--brand-dark); }
.download-button.secondary { color: var(--ink); background: var(--surface); border-color: var(--line); }
.download-button.secondary:hover { border-color: #a9c8b7; }

.download-hint {
  grid-column: 1 / -1;
  margin: -8px 0 0;
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}

.screens-section { padding: 30px 0 38px; }

.section-heading {
  display: flex;
  margin-bottom: 18px;
  align-items: baseline;
  justify-content: space-between;
}

.section-heading h2 { margin: 0; font-size: 22px; }
.section-heading span { color: var(--muted); font-size: 13px; }

.screenshots {
  display: grid;
  grid-auto-columns: minmax(178px, 68%);
  grid-auto-flow: column;
  gap: 16px;
  overflow-x: auto;
  padding: 2px 2px 16px;
  scroll-snap-type: x mandatory;
  scrollbar-color: #b9c9bf transparent;
}

.screenshot {
  width: 100%;
  aspect-ratio: 9 / 16;
  border: 1px solid var(--line);
  border-radius: 8px;
  object-fit: cover;
  object-position: top;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(22, 43, 31, .08);
  scroll-snap-align: start;
}

.page-footer {
  display: flex;
  gap: 8px 24px;
  padding: 22px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
  flex-wrap: wrap;
}

.page-footer strong { color: #4d5751; }

.browser-guide {
  position: fixed;
  inset: 0;
  z-index: 100;
  padding: 84px 28px 28px;
  color: white;
  background: rgba(17, 23, 20, .9);
}

.browser-guide button {
  position: absolute;
  top: 18px;
  left: 18px;
  width: 42px;
  height: 42px;
  border: 0;
  color: white;
  background: transparent;
  font-size: 34px;
  cursor: pointer;
}

.guide-arrow { position: absolute; top: 12px; right: 24px; font-size: 64px; }
.guide-step { display: flex; gap: 12px; margin: 20px auto; max-width: 360px; align-items: center; font-size: 17px; }
.guide-step b { display: grid; width: 28px; height: 28px; border-radius: 50%; place-items: center; background: var(--brand); }

.load-error {
  position: fixed;
  inset: 0;
  display: grid;
  gap: 14px;
  place-content: center;
  text-align: center;
  background: var(--page);
}

.load-error button { padding: 10px 18px; border: 0; border-radius: 8px; color: white; background: var(--brand); cursor: pointer; }

[hidden] { display: none !important; }

@media (max-width: 380px) {
  .page-shell { padding-inline: 16px; }
  .app-intro { grid-template-columns: 72px minmax(0, 1fr); gap: 14px; }
  .app-icon { width: 72px; height: 72px; border-radius: 16px; }
  h1 { font-size: 26px; }
  .screenshots { grid-auto-columns: 72%; }
  .section-heading span { display: none; }
}