:root {
  --bg: #f6f4ef;
  --surface: #ffffff;
  --ink: #1f2623;
  --muted: #5c6662;
  --line: #dcd8cf;
  --accent: #2f4a43;
  --accent-soft: #e4ebe7;
  --max: 880px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #151918;
    --surface: #1c2220;
    --ink: #e9ece9;
    --muted: #a3ada8;
    --line: #2e3633;
    --accent: #9cc2b5;
    --accent-soft: #233029;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", "Yu Gothic", "Meiryo", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.9;
  letter-spacing: 0.02em;
}

a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }

.wrap { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* header */
.site-header { border-bottom: 1px solid var(--line); }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; flex-wrap: wrap; }
.brand { font-weight: 700; letter-spacing: 0.24em; text-decoration: none; color: var(--ink); font-size: 18px; }
.nav { display: flex; gap: 20px; flex-wrap: wrap; font-size: 14px; }
.nav a { color: var(--muted); text-decoration: none; }
.nav a:hover { color: var(--ink); }

/* hero */
.hero { padding: 112px 0 96px; }
.hero .eyebrow { margin: 0 0 20px; color: var(--muted); font-size: 13px; letter-spacing: 0.3em; }
.hero h1 { margin: 0; font-size: clamp(32px, 6vw, 52px); line-height: 1.45; font-weight: 600; letter-spacing: 0.08em; }
.hero p.lead { margin: 32px 0 0; max-width: 34em; color: var(--muted); }

/* sections */
section.block { padding: 72px 0; border-top: 1px solid var(--line); }
section.block h2 { margin: 0 0 8px; font-size: 13px; letter-spacing: 0.3em; color: var(--muted); font-weight: 600; }
section.block h3.title { margin: 0 0 28px; font-size: 24px; line-height: 1.6; font-weight: 600; }

.values { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin: 0; padding: 0; list-style: none; }
.values li { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 24px; }
.values strong { display: block; margin-bottom: 8px; font-size: 17px; }
.values span { color: var(--muted); font-size: 15px; }

.note { background: var(--accent-soft); border-radius: 12px; padding: 20px 24px; color: var(--ink); }

/* document pages */
.doc { padding: 64px 0 96px; }
.doc h1 { font-size: 28px; line-height: 1.5; margin: 0 0 8px; }
.doc .meta { color: var(--muted); font-size: 14px; margin: 0 0 40px; }
.doc h2 { font-size: 19px; margin: 48px 0 12px; padding-top: 8px; border-top: 1px solid var(--line); }
.doc h3 { font-size: 16px; margin: 28px 0 8px; }
.doc p, .doc li { font-size: 15.5px; }
.doc ul, .doc ol { padding-left: 1.4em; }
.doc .lang-en { margin-top: 64px; }
.doc blockquote { margin: 16px 0; padding: 14px 18px; border-left: 3px solid var(--accent); background: var(--surface); }

/* footer */
.site-footer { border-top: 1px solid var(--line); padding: 32px 0 48px; color: var(--muted); font-size: 13px; }
.site-footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.site-footer a { color: var(--muted); }

@media (max-width: 560px) {
  .hero { padding: 72px 0 64px; }
  section.block { padding: 56px 0; }
  .nav { gap: 14px; }
}

code { font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace; font-size: 0.9em; background: var(--accent-soft); padding: 1px 6px; border-radius: 4px; }
.doc p, .doc li, .doc blockquote, code { overflow-wrap: anywhere; }

@media (max-width: 560px) { .br-wide { display: none; } }