:root {
  --bg: #f7f1e7;
  --surface: #fffdf8;
  --text: #272422;
  --muted: #6f6761;
  --line: #ddd2c2;
  --link: #1e5aa7;
  --jp-font-stack: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "Yu Gothic", "YuGothic", "Meiryo", "Noto Sans JP", sans-serif;
}
html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--jp-font-stack);
}
body {
  line-height: 1.8;
}
main {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 20px 64px;
}
.header {
  margin-bottom: 24px;
}
.brand {
  display: inline-block;
  margin-bottom: 12px;
  color: var(--link);
  text-decoration: none;
  font-weight: 700;
}
.brand:hover { text-decoration: underline; }
h1 {
  margin: 0;
  font-size: 30px;
  line-height: 1.3;
  font-weight: 800;
}
.intro {
  margin-top: 12px;
  color: var(--muted);
  font-size: 14px;
}
section {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px 18px 14px;
}
section + section {
  margin-top: 16px;
}
h2 {
  margin: 0 0 10px;
  font-size: 24px;
  line-height: 1.45;
  font-weight: 800;
}
p {
  margin: 0 0 10px;
  font-size: 16px;
}
p:last-child {
  margin-bottom: 0;
}
.footer {
  margin-top: 20px;
  color: var(--muted);
  font-size: 13px;
}
@media (max-width: 640px) {
  main {
    padding: 18px 14px 48px;
  }
  h1 {
    font-size: 26px;
  }
  h2 {
    font-size: 22px;
  }
  p {
    font-size: 15px;
  }
}