:root {
  --bg: #f7fbf9;
  --text: #0b1f16;
  --muted: #5a7a6c;
  --brand: #21c58e;
  --accent: #2bd4a3;
  --card: #ffffff;
  --border: #cfe5da;
  --radius: 14px;
}
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "PingFang SC", "Microsoft YaHei";
  color: var(--text);
  background:
    radial-gradient(800px 380px at 12% -8%, rgba(33,197,142,0.12) 0%, rgba(33,197,142,0.0) 60%),
    linear-gradient(180deg, #ffffff 0%, var(--bg) 100%);
}
.nav { position: sticky; top: 0; background: rgba(255,255,255,0.82); border-bottom: 1px solid var(--border); backdrop-filter: blur(8px); }
.container { max-width: 880px; margin: 0 auto; padding: 0 20px; }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; }
.brand-mark { width: 24px; height: 24px; border-radius: 8px; background: linear-gradient(180deg, var(--brand), var(--accent)); }
.main { padding: 40px 0 60px; }
h1 { font-size: clamp(24px, 4.6vw, 32px); margin: 0 0 10px; }
.subtitle { color: var(--muted); margin-bottom: 24px; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
h2 { font-size: 18px; margin: 18px 0 8px; }
p, li { color: var(--text); line-height: 1.7; }
ul { margin: 8px 0 16px; padding-left: 18px; }
.footer { color: var(--muted); border-top: 1px solid var(--border); padding: 24px 0 36px; margin-top: 28px; }
a { color: var(--brand); text-decoration: none; }

body.embed .nav, body.embed .footer { display: none; }
body.embed .main { padding: 10px 0 20px; }

body.plain .nav, body.plain .footer { display: none; }
body.plain .container { max-width: none; padding: 0 12px; }
body.plain .card { background: transparent; border: none; border-radius: 0; padding: 0; }