html {
  font-family:
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    "Yu Gothic",
    "YuGothic",
    "Hiragino Kaku Gothic ProN",
    "Noto Sans JP",
    sans-serif;

  line-height: 1.8;
  color: #222;
  background: #f8f8f6;
}

body {
  margin: 0;
}

/* サイト全体 */

header,
main,
footer {
  max-width: 900px;
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* ヘッダー */

header {
  padding-top: 36px;
  padding-bottom: 24px;
}

header h1 {
  margin: 0 0 18px;
  font-size: 1.7rem;
  font-weight: 600;
}

header h1 a {
  color: #111;
  text-decoration: none;
}

/* ナビゲーション */

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  font-size: 0.95rem;
}

nav a {
  color: #333;
  text-decoration: none;
}

nav a:hover {
  text-decoration: underline;
}

/* 本文 */

main {
  max-width: 760px;
  padding-top: 40px;
  padding-bottom: 80px;
}

main h1 {
  font-size: 2rem;
  line-height: 1.4;
  margin-top: 0;
  margin-bottom: 32px;
}

main h2 {
  font-size: 1.45rem;
  margin-top: 2.8em;
  margin-bottom: 1em;
}

main h3 {
  font-size: 1.15rem;
  margin-top: 2.2em;
}

p {
  margin: 1.2em 0;
}

ul,
ol {
  padding-left: 1.5em;
}

li {
  margin: 0.45em 0;
}

/* リンク */

main a {
  color: #1d4f91;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

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

/* 引用 */

blockquote {
  margin: 2em 0;
  padding: 0.2em 1.4em;
  border-left: 4px solid #bbb;
  color: #555;
}

/* 横線 */

hr {
  border: 0;
  border-top: 1px solid #ddd;
}

/* フッター */

footer {
  padding-top: 24px;
  padding-bottom: 48px;
  font-size: 0.85rem;
  color: #666;
}

/* スマートフォン */

@media (max-width: 600px) {
  header,
  main,
  footer {
    padding-left: 18px;
    padding-right: 18px;
  }

  header {
    padding-top: 24px;
  }

  main {
    padding-top: 28px;
  }

  main h1 {
    font-size: 1.65rem;
  }

  main h2 {
    font-size: 1.3rem;
  }

  nav {
    gap: 6px 14px;
  }
}

/* トップページ */

.hero {
  margin-bottom: 64px;
}

.hero h1 {
  margin-bottom: 24px;
}

.intro {
  font-size: 1.05rem;
}

.home-section {
  margin-top: 56px;
}

.home-section h2 {
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid #ddd;
}

.home-section p {
  color: #555;
}

.home-links {
  list-style: none;
  padding: 0;
  margin: 20px 0 0;
}

.home-links li {
  margin: 10px 0;
}

.home-links a {
  display: inline-block;
  font-weight: 500;
}