:root {
  color-scheme: light dark;
  --brand: #2854e8;
  --brand-strong: #1839a8;
  --accent: #ff6865;
  --ink: #15203a;
  --muted: #59647a;
  --surface: #ffffff;
  --background: #f4f6fb;
  --line: #dfe4ef;
  --shadow: 0 18px 50px rgba(34, 57, 115, 0.10);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--background);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic UI",
    "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 16px;
  line-height: 1.85;
  overflow-wrap: anywhere;
}

a {
  color: var(--brand);
  text-underline-offset: 0.18em;
}

a:hover {
  text-decoration-thickness: 2px;
}

.site-header {
  background: rgba(244, 246, 251, 0.94);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(18px);
}

.header-inner,
.container {
  width: min(100% - 32px, 900px);
  margin-inline: auto;
}

.header-inner {
  min-height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 1.08rem;
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
}

nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px 18px;
  font-size: 0.9rem;
  font-weight: 650;
}

nav a {
  color: var(--muted);
  text-decoration: none;
}

nav a[aria-current="page"],
nav a:hover {
  color: var(--brand);
}

main {
  padding: 58px 0 72px;
}

.hero {
  padding: 48px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--brand);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.4;
  letter-spacing: -0.025em;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 7vw, 3.6rem);
}

h2 {
  margin: 2.8em 0 0.8em;
  font-size: clamp(1.35rem, 4vw, 1.8rem);
  scroll-margin-top: 90px;
}

h3 {
  margin: 1.5em 0 0.4em;
  font-size: 1.06rem;
}

p,
ul,
ol {
  margin: 0.8em 0;
}

.lead {
  max-width: 700px;
  margin-top: 18px;
  color: var(--muted);
  font-size: 1.08rem;
}

.effective-date {
  display: inline-block;
  margin-top: 22px;
  padding: 6px 12px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--brand) 10%, transparent);
  color: var(--brand-strong);
  font-size: 0.86rem;
  font-weight: 700;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 28px;
}

.card {
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
}

.card h2,
.card h3 {
  margin-top: 0;
}

.card p {
  color: var(--muted);
}

.card-link {
  display: inline-block;
  margin-top: 8px;
  font-weight: 750;
}

.notice {
  margin: 28px 0;
  padding: 18px 20px;
  border-left: 4px solid var(--accent);
  border-radius: 4px 14px 14px 4px;
  background: color-mix(in srgb, var(--accent) 9%, var(--surface));
}

.document {
  padding: 38px 48px 52px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.document > h2 {
  padding-top: 0.2em;
  border-top: 1px solid var(--line);
}

.document ul,
.document ol {
  padding-left: 1.45em;
}

.contact-box {
  margin-top: 36px;
  padding: 22px;
  border-radius: 18px;
  background: color-mix(in srgb, var(--brand) 8%, var(--surface));
}

.small {
  color: var(--muted);
  font-size: 0.88rem;
}

footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
}

.footer-inner {
  width: min(100% - 32px, 900px);
  margin-inline: auto;
  padding: 24px 0 38px;
}

@media (max-width: 720px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 10px;
    padding: 12px 0;
  }

  nav {
    justify-content: flex-start;
  }

  main {
    padding-top: 28px;
  }

  .hero,
  .document {
    padding: 28px 22px 36px;
    border-radius: 22px;
  }

  .grid {
    grid-template-columns: 1fr;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --brand: #7da2ff;
    --brand-strong: #b8cbff;
    --accent: #ff817d;
    --ink: #f6f7fb;
    --muted: #b1b8ca;
    --surface: #171a23;
    --background: #0d0f15;
    --line: #2b3040;
    --shadow: none;
  }

  .site-header {
    background: rgba(13, 15, 21, 0.92);
  }
}

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