:root {
  color-scheme: light;
  --ink: #151515;
  --muted: #626262;
  --line: #dedede;
  --surface: #f6f6f6;
  --accent: #ff0033;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: #fff;
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", sans-serif;
  line-height: 1.75;
}

.container {
  width: min(760px, calc(100% - 40px));
  margin: 0 auto;
  padding: 72px 0 40px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(34px, 7vw, 56px);
  line-height: 1.15;
  letter-spacing: -.04em;
}

h2 {
  margin: 0 0 10px;
  font-size: 22px;
  line-height: 1.4;
}

.lead {
  max-width: 650px;
  margin: 22px 0 38px;
  color: var(--muted);
  font-size: 18px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.card {
  display: flex;
  min-height: 130px;
  padding: 24px;
  flex-direction: column;
  justify-content: space-between;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  color: inherit;
  text-decoration: none;
}

.card strong { font-size: 20px; }
.card span { color: var(--muted); }
.card:hover { border-color: #aaa; }

.back {
  display: inline-block;
  margin-bottom: 42px;
  color: var(--muted);
  text-decoration: none;
}

.document h1 { font-size: clamp(34px, 6vw, 48px); }
.updated { margin: 12px 0 40px; color: var(--muted); }

.ja { margin-top: -20px; }

.language-nav {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  margin: 0 0 34px;
}

.language-nav a {
  padding: 5px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink);
  text-decoration: none;
}

.language-section {
  margin-top: 72px;
  padding-top: 58px;
  border-top: 3px solid var(--ink);
}

section {
  padding: 28px 0;
  border-top: 1px solid var(--line);
}

section p:last-child,
section ul:last-child { margin-bottom: 0; }

code {
  padding: 2px 6px;
  border-radius: 5px;
  background: var(--surface);
  font-size: .92em;
}

a { color: #075bc7; }

.button {
  display: inline-block;
  padding: 10px 16px;
  border-radius: 9px;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
}

footer {
  margin-top: 56px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 600px) {
  .container { padding-top: 44px; }
  .cards { grid-template-columns: 1fr; }
}