:root {
  color-scheme: light;
  --paper: #f7f4ed;
  --paper-deep: #ede7da;
  --ink: #24231f;
  --ink-soft: #6f6b62;
  --line: rgba(36, 35, 31, 0.12);
  --accent: #3f9e7d;
  --accent-soft: #e2f2ea;
  --white: rgba(255, 255, 255, 0.72);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at 82% 8%, rgba(63, 158, 125, 0.14), transparent 32rem),
    linear-gradient(180deg, #fbfaf6 0%, var(--paper) 100%);
  line-height: 1.75;
}

a { color: inherit; }

.shell {
  width: min(720px, calc(100% - 40px));
  margin: 0 auto;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 28px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-decoration: none;
}

.mark {
  width: 28px;
  height: 28px;
  border: 1px solid rgba(63, 158, 125, 0.35);
  border-radius: 50%;
  background: radial-gradient(circle at 50% 70%, #f8c85d 0 8%, #4fb58d 9% 23%, #eef6f1 24% 48%, transparent 49%);
  box-shadow: inset 0 0 18px rgba(63, 158, 125, 0.14);
}

nav { display: flex; gap: 18px; }

nav a,
.footer-links a {
  color: var(--ink-soft);
  font-size: 13px;
  text-decoration: none;
}

nav a:hover,
.footer-links a:hover { color: var(--ink); }

main { padding: 64px 0 88px; }

.hero { padding: 48px 0 72px; }

.eyebrow {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1 {
  max-width: 650px;
  margin: 0;
  font-family: ui-serif, "Hiragino Mincho ProN", "Yu Mincho", serif;
  font-size: clamp(38px, 8vw, 66px);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1.18;
}

.lead {
  max-width: 570px;
  margin: 26px 0 0;
  color: var(--ink-soft);
  font-size: clamp(16px, 2.5vw, 19px);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}

.button.secondary {
  border-color: var(--line);
  background: var(--white);
  color: var(--ink);
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--white);
  backdrop-filter: blur(18px);
}

.card .number {
  color: var(--accent);
  font-size: 12px;
  font-weight: 750;
  letter-spacing: 0.12em;
}

.card h2 { margin: 14px 0 8px; font-size: 17px; }
.card p { margin: 0; color: var(--ink-soft); font-size: 14px; }

.document {
  padding: 34px clamp(22px, 5vw, 46px);
  border: 1px solid var(--line);
  border-radius: 26px;
  background: var(--white);
  box-shadow: 0 24px 80px rgba(36, 35, 31, 0.05);
}

.document h1 { font-size: clamp(32px, 7vw, 48px); }
.document h2 { margin: 42px 0 12px; font-size: 20px; }
.document h3 { margin: 32px 0 10px; font-size: 16px; }
.document p, .document li { color: #4f4c46; }
.document ul { padding-left: 1.25rem; }
.document .updated { margin: 10px 0 30px; color: var(--ink-soft); font-size: 13px; }
.document hr { margin: 48px 0; border: 0; border-top: 1px solid var(--line); }

.notice {
  margin: 28px 0 0;
  padding: 18px 20px;
  border-radius: 16px;
  background: var(--accent-soft);
  color: #2f7a5d;
  font-size: 14px;
}

footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 30px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 12px;
}

.footer-links { display: flex; flex-wrap: wrap; gap: 16px; }

@media (max-width: 640px) {
  nav { display: none; }
  main { padding-top: 34px; }
  .hero { padding-top: 34px; }
  .grid { grid-template-columns: 1fr; }
  footer { align-items: flex-start; flex-direction: column-reverse; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}