body {
  font-family:
    system-ui,
    -apple-system,
    'Segoe UI',
    Roboto,
    sans-serif;
  max-width: 760px;
  margin: 0 auto;
  padding: 24px 18px 48px;
  line-height: 1.55;
  color: #1f2a25;
  background: #f6f4ee;
}
header {
  margin-bottom: 18px;
}
header .brand {
  font-weight: 900;
  color: #0f3d2e;
  letter-spacing: 1px;
  text-decoration: none;
  font-size: 18px;
}
h1 {
  font-size: 1.7rem;
  margin: 0.4rem 0 0.2rem;
  color: #0f3d2e;
}
h2 {
  font-size: 1.15rem;
  margin: 1.6rem 0 0.5rem;
  color: #0f3d2e;
  border-bottom: 1px solid #d9d4c5;
  padding-bottom: 4px;
}
h3 {
  font-size: 1rem;
  margin: 1rem 0 0.3rem;
}
.meta {
  color: #5b665f;
  font-size: 0.9rem;
}
.box {
  background: #fff;
  border: 1px solid #d9d4c5;
  border-radius: 10px;
  padding: 12px 16px;
  margin: 14px 0;
}
.fill {
  background: #fff3c4;
  border: 1px dashed #b8860b;
  padding: 0 4px;
  border-radius: 4px;
}
nav.toc ol {
  columns: 2;
  gap: 18px;
  padding-left: 20px;
  font-size: 0.92rem;
}
nav.toc a {
  color: #0f3d2e;
}
ul,
ol {
  padding-left: 22px;
}
li {
  margin: 4px 0;
}
footer {
  margin-top: 32px;
  font-size: 0.9rem;
  color: #5b665f;
  border-top: 1px solid #d9d4c5;
  padding-top: 12px;
}
a {
  color: #0f3d2e;
}
@media (max-width: 600px) {
  nav.toc ol {
    columns: 1;
  }
}