:root {
  --bg: #ffffff;
  --fg: #171c26;
  --muted: #5d6572;
  --rule: #e3e6ea;
  --link: #171c26;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #171c26;
    --fg: #eef0f3;
    --muted: #9aa2ae;
    --rule: #2b323e;
    --link: #eef0f3;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0 auto;
  padding: 4rem 1.5rem 6rem;
  max-width: 44rem;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  font-size: 16px;
  line-height: 1.9;
  -webkit-text-size-adjust: 100%;
}

header {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--rule);
}

h1 {
  margin: 0;
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.tagline {
  margin: 0.25rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.meta {
  color: var(--muted);
  font-size: 0.9rem;
}

section {
  margin-top: 3rem;
}

h2 {
  margin: 0 0 1rem;
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

h3 {
  margin: 2rem 0 0.5rem;
  font-size: 1rem;
  font-weight: 600;
}

p {
  margin: 0 0 1rem;
}

ul {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
}

li {
  margin-bottom: 0.35rem;
}

code {
  padding: 0.1em 0.35em;
  border-radius: 4px;
  background: var(--rule);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.9em;
}

a {
  color: var(--link);
  text-underline-offset: 0.2em;
}

footer {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.9rem;
}

footer p {
  margin: 0 0 0.35rem;
}

.copyright {
  color: var(--muted);
}