:root {
  color-scheme: dark;
  --bg: #090b0d;
  --surface: #121518;
  --surface-raised: #181c20;
  --line: #2a3035;
  --text: #f5f4ef;
  --muted: #92999e;
  --accent: #d7ff3f;
  --danger: #ff6b62;
  font-family: Inter, "Noto Sans JP", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 50% -12%, rgba(215, 255, 63, .1), transparent 32rem),
    var(--bg);
  color: var(--text);
  line-height: 1.8;
}
a { color: inherit; }

.site-header {
  height: 72px;
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 max(22px, env(safe-area-inset-left));
  border-bottom: 1px solid rgba(255, 255, 255, .06);
  background: rgba(9, 11, 13, .88);
  backdrop-filter: blur(18px);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 21px;
  font-weight: 900;
  letter-spacing: .12em;
  line-height: 1;
  text-decoration: none;
}
.brand-mark {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  background: var(--accent);
  color: var(--bg);
  font-size: 18px;
  font-weight: 1000;
  transform: skew(-7deg);
}
.header-link {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
}
.header-link:hover { color: var(--accent); }

.page {
  width: min(100% - 40px, 820px);
  margin: 0 auto;
  padding: 72px 0 96px;
}
.page-header { margin-bottom: 40px; }
.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: .2em;
}
h1 {
  max-width: 700px;
  margin: 0;
  font-size: clamp(34px, 7vw, 58px);
  line-height: 1.14;
  letter-spacing: -.05em;
}
.lead {
  max-width: 680px;
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 14px;
}
.updated {
  display: inline-flex;
  margin-top: 22px;
  padding: 7px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .08em;
}

.document {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: linear-gradient(145deg, rgba(255,255,255,.025), transparent 28%), var(--surface);
}
.section {
  padding: 30px clamp(20px, 5vw, 40px);
  border-bottom: 1px solid var(--line);
}
.section:last-child { border-bottom: 0; }
.section-number {
  display: block;
  margin-bottom: 8px;
  color: var(--accent);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: .16em;
}
h2 {
  margin: 0 0 14px;
  font-size: 20px;
  line-height: 1.45;
  letter-spacing: -.025em;
}
h3 { margin: 24px 0 7px; font-size: 14px; }
p { margin: 0; }
.section p, .section li { color: #c2c6c8; font-size: 13px; }
.section p + p { margin-top: 12px; }
ul, ol { margin: 12px 0 0; padding-left: 1.3rem; }
li + li { margin-top: 7px; }
strong { color: var(--text); }
.note {
  margin-top: 18px;
  padding: 16px;
  border-left: 3px solid var(--accent);
  background: rgba(215, 255, 63, .055);
  color: #d9ddca !important;
}
.danger-note { border-left-color: var(--danger); background: rgba(255, 107, 98, .055); }

.steps { counter-reset: steps; list-style: none; padding: 0; }
.steps li {
  position: relative;
  min-height: 48px;
  padding: 3px 0 20px 58px;
}
.steps li::before {
  counter-increment: steps;
  content: counter(steps, decimal-leading-zero);
  width: 40px;
  height: 40px;
  position: absolute;
  top: 0;
  left: 0;
  display: grid;
  place-items: center;
  border: 1px solid var(--accent);
  border-radius: 12px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 900;
}
.steps li:last-child { padding-bottom: 0; }

.action-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 18px;
  padding: 13px 18px;
  border-radius: 12px;
  background: var(--accent);
  color: var(--bg);
  font-size: 12px;
  font-weight: 900;
  text-decoration: none;
}
.action-link:hover { filter: brightness(.92); }

.home-hero { padding-top: 96px; padding-bottom: 52px; }
.home-hero h1 span { color: var(--accent); }
.link-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}
.link-card {
  min-height: 190px;
  display: flex;
  flex-direction: column;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease;
}
.link-card:hover { transform: translateY(-3px); border-color: var(--accent); }
.link-card small { color: var(--accent); font-size: 10px; font-weight: 900; letter-spacing: .16em; }
.link-card strong { margin-top: 34px; font-size: 18px; line-height: 1.45; }
.link-card span { margin-top: auto; color: var(--muted); font-size: 11px; }

.site-footer {
  padding: 30px 20px calc(30px + env(safe-area-inset-bottom));
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 10px;
  text-align: center;
}
.footer-links { display: flex; justify-content: center; flex-wrap: wrap; gap: 18px; margin-bottom: 14px; }
.footer-links a { text-decoration: none; }
.footer-links a:hover { color: var(--accent); }

@media (max-width: 680px) {
  .page { width: min(100% - 28px, 820px); padding-top: 48px; }
  .link-grid { grid-template-columns: 1fr; }
  .link-card { min-height: 142px; }
  .link-card strong { margin-top: 22px; }
  .site-header { padding-inline: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .link-card { transition: none; }
}