:root {
  --bg: #fffbf5;
  --surface: #ffffff;
  --text: #2b2622;
  --muted: #7d756c;
  --border: #f0e8dd;
  --tint: #ff8a5b;
  --tint-ink: #e25f2c;
  --radius: 16px;
  --maxw: 760px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161310;
    --surface: #211d19;
    --text: #f3ede5;
    --muted: #a89e92;
    --border: #322c25;
    --tint: #ff9a70;
    --tint-ink: #ffb291;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--tint-ink); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  height: 60px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; color: var(--text); }
.brand img { width: 30px; height: 30px; border-radius: 8px; }
.site-header nav { margin-left: auto; display: flex; align-items: center; gap: 18px; }
.site-header nav a { color: var(--muted); font-size: 14px; }
.site-header nav a:hover { color: var(--text); text-decoration: none; }

.lang-toggle {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 999px;
  padding: 5px 12px;
  font-size: 13px;
  cursor: pointer;
  font-family: inherit;
}
.lang-toggle:hover { border-color: var(--tint); }

/* Hero */
.hero { text-align: center; padding: 64px 20px 48px; }
.hero img.appicon { width: 96px; height: 96px; border-radius: 22px; box-shadow: 0 12px 32px rgba(0,0,0,.12); }
.hero h1 { font-size: 40px; line-height: 1.15; margin: 24px 0 8px; letter-spacing: -.02em; }
.hero .tagline { font-size: 19px; color: var(--muted); margin: 0 auto; max-width: 30em; }
.cta { display: inline-flex; align-items: center; gap: 8px; margin-top: 28px;
  background: var(--tint); color: #fff; padding: 13px 26px; border-radius: 999px;
  font-weight: 600; font-size: 16px; }
.cta:hover { text-decoration: none; opacity: .92; }

/* Sections */
main { padding: 40px 0 24px; }
section { margin: 0 0 40px; }
h2 { font-size: 24px; margin: 0 0 16px; letter-spacing: -.01em; }
h3 { font-size: 17px; margin: 24px 0 6px; }
p { margin: 0 0 14px; }
.muted { color: var(--muted); }
small { color: var(--muted); }

/* Feature grid */
.features { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.feature { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
.feature .ico { font-size: 26px; line-height: 1; }
.feature h3 { margin: 12px 0 4px; }
.feature p { margin: 0; font-size: 14px; color: var(--muted); }

/* FAQ / prose card */
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 8px 24px; }
details { border-bottom: 1px solid var(--border); padding: 16px 0; }
details:last-child { border-bottom: 0; }
summary { cursor: pointer; font-weight: 600; list-style: none; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "＋"; float: right; color: var(--muted); }
details[open] summary::after { content: "－"; }
details p { margin: 12px 0 0; color: var(--muted); }

.contact-box { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; text-align: center; }
.contact-box .email { font-size: 20px; font-weight: 700; }

/* Legal prose */
.prose h2 { margin-top: 36px; }
.prose ul { padding-left: 1.2em; }
.prose li { margin: 6px 0; }
table.data { width: 100%; border-collapse: collapse; font-size: 14px; margin: 12px 0; }
table.data th, table.data td { border: 1px solid var(--border); padding: 8px 10px; text-align: left; }
table.data th { background: var(--bg); }

/* Footer */
.site-footer { border-top: 1px solid var(--border); padding: 32px 0; margin-top: 24px; color: var(--muted); font-size: 14px; }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 16px; align-items: center; }
.site-footer nav { margin-left: auto; display: flex; gap: 18px; flex-wrap: wrap; }
.site-footer a { color: var(--muted); }

/* Language visibility — toggled by lang.js via <html data-lang> */
html[data-lang="en"] .lang-zh { display: none; }
html[data-lang="zh"] .lang-en { display: none; }

@media (max-width: 560px) {
  .hero h1 { font-size: 32px; }
  .features { grid-template-columns: 1fr; }
  .site-header nav { gap: 12px; }
  .site-header nav a:not(.lang-toggle) { display: none; }
}