:root {
  color-scheme: light;
  --bg: #ffffff;
  --ink: #142033;
  --muted: #667085;
  --line: #d9e2ec;
  --soft: #f5f8fb;
  --navy: #102a43;
  --blue: #2563eb;
  --green: #dff7ea;
  --green-ink: #176047;
  --code: #0f172a;
  --code-line: #243247;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.8;
}

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

a:hover {
  text-decoration: underline;
}

.site-header {
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner,
.footer-inner,
main {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  color: var(--navy);
  display: grid;
  gap: 0;
  flex: 0 0 auto;
}

.brand strong {
  font-size: 18px;
  line-height: 1.2;
}

.brand span {
  font-size: 12px;
  color: var(--muted);
}

.global-nav {
  display: flex;
  gap: 14px;
  align-items: center;
  overflow-x: auto;
  white-space: nowrap;
  padding: 14px 0;
  font-size: 14px;
}

.global-nav a {
  color: var(--ink);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.65fr);
  gap: 36px;
  align-items: center;
  padding: 52px 0 34px;
}

.eyebrow {
  color: var(--green-ink);
  font-weight: 700;
  margin: 0 0 12px;
  font-size: 14px;
}

h1,
h2,
h3 {
  color: var(--navy);
  line-height: 1.35;
  letter-spacing: 0;
}

h1 {
  font-size: clamp(32px, 6vw, 54px);
  margin: 0 0 18px;
}

h2 {
  font-size: 28px;
  margin: 48px 0 16px;
}

h3 {
  font-size: 18px;
  margin: 0 0 8px;
}

.lead {
  font-size: 18px;
  color: #344054;
  margin: 0 0 22px;
}

.notice-list {
  display: grid;
  gap: 10px;
  margin-top: 22px;
}

.notice-list p {
  margin: 0;
  padding: 12px 14px;
  border: 1px solid var(--line);
  background: var(--soft);
  border-radius: 8px;
  font-size: 14px;
}

.code-panel {
  background: var(--code);
  color: #e6edf7;
  border-radius: 8px;
  padding: 18px;
  box-shadow: 0 18px 48px rgba(16, 42, 67, 0.16);
}

.code-panel span {
  display: block;
  color: #9cc6ff;
  font-size: 13px;
  margin-bottom: 10px;
}

pre {
  overflow-x: auto;
  margin: 18px 0;
  padding: 18px;
  border-radius: 8px;
  background: var(--code);
  color: #edf5ff;
  line-height: 1.65;
}

.code-panel pre {
  margin: 0;
  padding: 14px;
  background: var(--code-line);
}

code {
  font-family: Consolas, "SFMono-Regular", Menlo, monospace;
  font-size: 14px;
}

.content {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  padding-bottom: 56px;
}

.content section,
.faq-block {
  border-top: 1px solid var(--line);
}

.toc {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--soft);
  padding: 18px 20px;
  margin: 8px 0 22px;
}

.toc strong {
  display: block;
  margin-bottom: 8px;
}

.toc ol {
  margin: 0;
  padding-left: 22px;
}

.check-list {
  display: grid;
  gap: 10px;
  padding: 0;
  list-style: none;
}

.check-list li {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px 14px 12px 42px;
  position: relative;
  background: #fff;
}

.check-list li::before {
  content: "";
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--green);
  border: 1px solid #9bd9b6;
  position: absolute;
  left: 16px;
  top: 18px;
}

.steps,
.link-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 18px 0;
}

.step-card,
.link-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  padding: 18px;
}

.step-card span {
  display: inline-grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: #e9f1ff;
  color: var(--blue);
  font-weight: 800;
  margin-bottom: 12px;
}

.step-card p {
  margin: 0;
}

.link-card {
  display: grid;
  gap: 6px;
  color: var(--ink);
}

.link-card span {
  color: var(--blue);
  font-weight: 800;
}

.link-card small {
  color: var(--muted);
  font-size: 14px;
}

details {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px 16px;
  margin: 10px 0;
  background: #fff;
}

summary {
  cursor: pointer;
  font-weight: 800;
  color: var(--navy);
}

.site-footer {
  border-top: 1px solid var(--line);
  background: var(--soft);
  padding: 32px 0;
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
}

.footer-inner p {
  color: var(--muted);
  font-size: 13px;
  margin: 8px 0 0;
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

@media (max-width: 820px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 0;
    padding-top: 14px;
  }

  .hero {
    grid-template-columns: 1fr;
    padding-top: 34px;
  }

  .steps,
  .link-grid,
  .footer-inner {
    grid-template-columns: 1fr;
  }

  h1 {
    font-size: 34px;
  }

  h2 {
    font-size: 24px;
  }
}


.news-list {
  display: grid;
  gap: 16px;
  margin: 18px 0;
}

.news-card,
.rule-box {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  padding: 18px;
}

.news-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  color: var(--muted);
  font-size: 14px;
  margin: 0 0 10px;
}

.news-meta span {
  color: var(--green-ink);
  background: var(--green);
  border-radius: 999px;
  padding: 3px 10px;
  font-weight: 800;
}

.news-card ul {
  margin-top: 10px;
}

.source-note {
  color: var(--muted);
  font-size: 14px;
}

.rules-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 18px 0;
}

@media (max-width: 820px) {
  .rules-grid {
    grid-template-columns: 1fr;
  }
}