:root {
  color-scheme: light;
  --bg: #f4f6fa;
  --panel: #ffffff;
  --header: #eef2f8;
  --line: #d5dde8;
  --fg: #1c2733;
  --fg-dim: #64748b;
  --accent: #2b6cb0;
  --accent-hover: #1f5c99;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.8 "Segoe UI", "Hiragino Sans", "Noto Sans JP", Meiryo, sans-serif;
}

a {
  color: var(--accent);
}

a:hover,
a:focus-visible {
  color: var(--accent-hover);
}

.page-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 24px max(24px, calc((100% - 880px) / 2));
  border-bottom: 1px solid var(--line);
  background: var(--header);
}

.page-header h1,
.page-header p {
  margin: 0;
}

.page-header h1 {
  color: #14375f;
  font-size: clamp(20px, 4vw, 28px);
}

.eyebrow {
  color: var(--fg-dim);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.page-header nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.page-header nav a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 5px 11px;
  border: 1px solid #b8c4d4;
  border-radius: 6px;
  background: #fff;
  color: #36556f;
  font-size: 13px;
  font-weight: 600;
  line-height: 1.2;
  text-decoration: none;
}

.page-header nav a:first-child {
  border-color: var(--accent);
  background: var(--accent);
  color: #fff;
}

.page-header nav a:hover,
.page-header nav a:focus-visible {
  border-color: var(--accent);
  background: #e7f0fa;
  color: var(--accent-hover);
}

.page-header nav a:first-child:hover,
.page-header nav a:first-child:focus-visible {
  border-color: var(--accent-hover);
  background: var(--accent-hover);
  color: #fff;
}

main,
footer {
  width: min(880px, calc(100% - 48px));
  margin-inline: auto;
}

main {
  padding: 32px 0 48px;
}

section {
  margin-bottom: 20px;
  padding: 20px 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

h2 {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 13px;
  letter-spacing: .08em;
}

p,
ul {
  margin: 8px 0;
}

footer {
  padding: 0 0 32px;
  color: var(--fg-dim);
  text-align: center;
}

@media (max-width: 680px) {
  .page-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .page-header nav {
    justify-content: flex-start;
  }

  main,
  footer {
    width: min(100% - 28px, 880px);
  }

  main {
    padding-top: 14px;
  }

  section {
    padding: 16px;
  }
}