:root {
  --bg: #ffffff;
  --bg-2: #f6f7f9;
  --card: #ffffff;
  --line: #e6e8eb;
  --ink: #111827;
  --muted: #5b6472;
  --accent: #0f766e;
  --alipay: #1677ff;
  --max: 1120px;
}

* { box-sizing: border-box; }

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "IBM Plex Sans", "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 28px 80px;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid var(--line);
}

.topbar-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 650;
  letter-spacing: -0.03em;
}

.brand:hover { text-decoration: none; }

.mark {
  width: 28px;
  height: 28px;
  border: 1px solid var(--ink);
  border-radius: 8px;
  display: grid;
  place-items: center;
  color: var(--ink);
  font-size: 15px;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px;
  font-size: 14px;
}

.nav a { color: var(--muted); }
.nav a[aria-current="page"],
.nav a:hover { color: var(--ink); text-decoration: none; }

.nav-cta { display: flex; gap: 10px; align-items: center; }

.btn,
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  padding: 9px 16px;
  font-size: 14px;
  border: 1px solid var(--line);
  color: var(--ink);
  text-decoration: none;
  background: #fff;
  cursor: pointer;
}

.btn:hover,
.btn-primary:hover { text-decoration: none; }

.btn-primary {
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}

.hero {
  padding: 72px 0 12px;
  background: var(--bg-2);
  border-bottom: 1px solid var(--line);
}

.kicker {
  color: var(--accent);
  font-size: 13px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin: 0 0 14px;
}

h1 {
  font-size: clamp(34px, 5vw, 52px);
  line-height: 1.15;
  letter-spacing: -0.035em;
  font-weight: 650;
  margin: 0 0 16px;
}

h2 {
  font-size: 26px;
  letter-spacing: -0.03em;
  margin: 48px 0 12px;
}

h3 { margin: 0 0 8px; font-size: 17px; }

.lead {
  font-size: 18px;
  color: var(--muted);
  max-width: 720px;
  margin: 0 0 24px;
}

.prose { max-width: 760px; }
.prose p { margin: 0 0 14px; color: var(--ink); }

.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 16px;
  overflow: hidden;
  margin: 36px 0 8px;
}

.stat {
  background: var(--card);
  padding: 22px 24px;
}

.stat b {
  display: block;
  font-size: 22px;
  letter-spacing: -0.03em;
}

.stat span { color: var(--muted); font-size: 13px; }

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }

.card,
.note,
.pay-box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px 22px;
}

.card p { color: var(--muted); margin: 0; }
.note { margin: 24px 0; color: var(--ink); background: var(--bg-2); }

ol { padding-left: 20px; }
li { margin: 8px 0; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0 28px;
  font-size: 14px;
}

th, td {
  border-bottom: 1px solid var(--line);
  padding: 12px 10px;
  text-align: left;
  vertical-align: top;
}

th { color: var(--muted); font-weight: 550; }

.price { font-variant-numeric: tabular-nums; white-space: nowrap; }

.tag {
  display: inline-block;
  font-size: 12px;
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--muted);
  white-space: nowrap;
}

.tag-live {
  border-color: #bbf7d0;
  background: #f0fdf4;
  color: #166534;
}

.cat { margin: 32px 0 40px; }
.cat h3 { font-size: 20px; margin-bottom: 6px; }
.cat .desc { color: var(--muted); margin: 0 0 12px; }

.foot {
  margin-top: 72px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
  display: grid;
  gap: 10px;
}

.foot nav { display: flex; flex-wrap: wrap; gap: 14px; }
.foot a { color: var(--muted); }

.pay-box { margin: 20px 0 28px; background: var(--bg-2); }
.pay-sum {
  font-size: 32px;
  font-weight: 650;
  letter-spacing: -0.03em;
  margin: 8px 0 18px;
}

.pay-method {
  display: flex;
  align-items: center;
  gap: 10px;
  border: 1px solid #1677ff;
  background: #eef5ff;
  padding: 12px 14px;
  margin: 12px 0 20px;
  border-radius: 10px;
}

.btn-pay {
  display: block;
  width: 100%;
  text-align: center;
  font-size: 17px;
  padding: 12px 16px;
  border: 0;
  border-radius: 10px;
  background: var(--alipay);
  color: #fff;
  cursor: pointer;
}

.btn-pay:hover { background: #0f66d8; }

code {
  font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
  font-size: 0.92em;
  background: var(--bg-2);
  padding: 1px 6px;
  border-radius: 4px;
}

.codeish {
  font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
  font-size: 13px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  overflow: auto;
  color: var(--ink);
  white-space: pre;
  line-height: 1.55;
}

@media (max-width: 800px) {
  .topbar-inner { flex-direction: column; align-items: flex-start; }
  .stats, .grid, .grid-2 { grid-template-columns: 1fr; }
  h1 { font-size: 32px; }
  .hero { padding-top: 40px; }
}