:root {
  color-scheme: light;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #172033;
  background: #f4f7fb;
}

* { box-sizing: border-box; }
body { margin: 0; line-height: 1.65; }
main {
  width: min(760px, calc(100% - 32px));
  margin: 40px auto;
  padding: 32px;
  background: #fff;
  border: 1px solid #dde5f0;
  border-radius: 20px;
  box-shadow: 0 12px 35px rgba(31, 55, 90, .08);
}
h1, h2 { line-height: 1.25; color: #153c75; }
h1 { margin-top: 0; }
h2 { margin-top: 28px; font-size: 1.15rem; }
a { color: #1859a9; }
.muted { color: #596579; }
.notice {
  padding: 14px 16px;
  border-left: 4px solid #2775d3;
  background: #eef6ff;
  border-radius: 8px;
}
nav { display: flex; gap: 16px; flex-wrap: wrap; margin-top: 28px; }
ul { padding-left: 22px; }
@media (max-width: 600px) {
  main { margin: 16px auto; padding: 22px; border-radius: 14px; }
}