body {
  margin: 0;
  background: #f7f7f4;
  color: #17201f;
  font: 16px/1.72 system-ui, -apple-system, "Microsoft YaHei", sans-serif;
}
main { width: min(780px, 88vw); margin: auto; padding: 72px 0 100px; }
a { color: #0f5c5d; }
h1, h2 { font-family: Georgia, "Songti SC", serif; letter-spacing: 0; }
h1 { font-size: clamp(38px, 7vw, 68px); line-height: 1.05; }
h2 { margin-top: 42px; font-size: 24px; }
small { color: #66716e; }
.back { display: inline-block; margin-bottom: 48px; }