@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

:root {
  color-scheme: dark;
  --bg: #02213b;
  --card: #072d4a;
  --fg: #f5fbff;
  --muted: #b4cad9;
  --accent: #62d2ff;
  --border: rgba(185, 226, 255, 0.24);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.75 "Plus Jakarta Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  -webkit-font-smoothing: antialiased;
}
header, main, footer { width: min(100% - 40px, 1000px); margin: 0 auto; }
header { padding: 22px 0; border-bottom: 1px solid var(--border); }
main > section { padding: 46px 0; border-bottom: 1px solid var(--border); }
footer { padding: 28px 0; color: var(--muted); font-size: 12px; }
a { color: var(--accent); text-underline-offset: 4px; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
p { margin: 0 0 18px; max-width: 76ch; }
h1, h2, h3 { line-height: 1.3; text-wrap: balance; }
h1 { font-size: clamp(34px, 5vw, 56px); max-width: 19ch; margin: 16px 0 22px; letter-spacing: -0.04em; }
:lang(ja) h1 { max-width: none; letter-spacing: 0; }
h2 { font-size: clamp(24px, 3vw, 32px); margin: 8px 0 24px; letter-spacing: -0.025em; }
h3 { font-size: 20px; margin: 0 0 18px; }
.container.nav, .brand, .links, .key-links { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.container.nav { justify-content: space-between; }
.brand { gap: 9px; font-weight: 700; font-size: 14px; }
.brand a, .links a { text-decoration: none; }
.brand-logo { display: block; height: 24px; width: auto; border-radius: 5px; }
.links { font-size: 13px; gap: 14px; }
.nav-toggle { display: none; }
.crumbs { margin-top: 20px; font-size: 12px; color: var(--muted); }
.crumbs a { color: inherit; }
.hero { background: radial-gradient(ellipse at 90% 10%, rgba(98, 210, 255, 0.09), transparent 60%); }
.hero-kicker, .label { color: var(--accent); font-size: 12px; letter-spacing: 0.09em; font-weight: 700; }
.hero-subline { font-size: 21px; line-height: 1.5; text-wrap: balance; }
.lead { font-size: 17px; color: var(--muted); max-width: 68ch; }
.status { font-size: 12px; font-weight: 600; color: var(--accent); }
.status span { margin: 0 8px; color: var(--muted); }
.key-links { gap: 12px 20px; font-size: 14px; }
.btn { display: inline-flex; border: 1px solid var(--border); border-radius: 5px; padding: 9px 14px; text-decoration: none; }
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
.card { padding: 26px; background: var(--card); border-top: 2px solid var(--accent); }
.card p { font-size: 15px; }
.card > :last-child { margin-bottom: 0; }
.card > a { font-size: 14px; }
.credit-loop { margin: 32px 0 0; border: 1px solid var(--border); padding: 24px; border-radius: 6px; }
.credit-loop figcaption { color: var(--muted); font-size: 12px; margin-bottom: 20px; }
.credit-loop ol { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px; }
.credit-loop li { position: relative; display: flex; flex-direction: column; gap: 7px; }
.credit-loop li:not(:last-child)::after { content: "\2192"; position: absolute; top: 26px; right: -18px; color: var(--accent); }
.step { font-size: 12px; font-weight: 700; color: var(--accent); }
.credit-loop strong { font-size: 15px; }
.credit-loop li > span:last-child { font-size: 13px; color: var(--muted); }
.loop-return { max-width: none; margin: 24px 0 0; padding-top: 14px; border-top: 1px dashed var(--accent); color: var(--accent); font-size: 13px; }
.closing-note { margin-top: 24px; margin-bottom: 0; color: var(--muted); font-size: 14px; }
.references p { font-size: 13px; }
.references h2 { font-size: 20px; }
.muted { color: var(--muted); }
.skip-link { position: absolute; left: 16px; top: -100px; padding: 10px; background: var(--card); z-index: 5; }
.skip-link:focus { top: 10px; }
@media (max-width: 720px) {
  .grid { grid-template-columns: 1fr; }
  main > section { padding: 34px 0; }
  .card { padding: 22px; }
  .credit-loop ol { grid-template-columns: 1fr; gap: 28px; }
  .credit-loop li { padding-left: 34px; }
  .step { position: absolute; left: 0; }
  .credit-loop li:not(:last-child)::after { content: "\2193"; top: auto; bottom: -24px; left: 0; right: auto; }
}
@media (max-width: 540px) {
  .container.nav { gap: 12px; }
  .nav-toggle { display: inline-flex; align-items: center; gap: 6px; background: transparent; color: var(--fg); border: 1px solid var(--border); border-radius: 5px; padding: 8px; }
  .links { display: none; width: 100%; padding: 10px; background: var(--card); }
  .links.open { display: flex; flex-direction: column; align-items: stretch; }
  .links a { padding: 8px; }
  .hero-subline { font-size: 18px; }
  .credit-loop { padding: 20px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
@media print {
  :root { --bg: #fff; --card: #fff; --fg: #111; --muted: #333; --accent: #164d70; --border: #999; color-scheme: light; }
  .nav-toggle, .links, .skip-link { display: none; }
  .hero { background: none; }
  .card, .credit-loop { break-inside: avoid; }
}