:root {
  --ink: #1d2733;
  --muted: #55606e;
  --accent: #1f5f8b;
  --accent-dark: #164766;
  --bg: #f7f8fa;
  --card: #ffffff;
  --line: #d9dee5;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
}

header.site,
main,
footer.site {
  max-width: 46rem;
  margin: 0 auto;
  padding: 0 1rem;
}

header.site {
  padding-top: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--line);
}

header.site a.brand {
  font-weight: bold;
  color: var(--ink);
  text-decoration: none;
}

nav.top {
  margin-top: 0.4rem;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.92rem;
}

nav.top a {
  margin-right: 0.9rem;
  color: var(--accent);
}

h1 {
  font-size: 1.8rem;
  line-height: 1.25;
  margin: 1.6rem 0 0.8rem;
}

h2 {
  font-size: 1.4rem;
  margin: 2.2rem 0 0.6rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.2rem;
}

h3 {
  font-size: 1.1rem;
  margin: 0 0 0.3rem;
}

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

article.qa {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1rem 1.2rem;
  margin: 1.2rem 0;
}

article.qa .cat {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  margin: 0 0 0.2rem;
}

article.qa p {
  margin: 0.5rem 0;
}

article.qa .tip {
  background: #eef4f9;
  border-left: 4px solid var(--accent);
  padding: 0.5rem 0.8rem;
}

ol.titles {
  padding-left: 1.6rem;
}

ol.titles li {
  margin-bottom: 0.3rem;
}

section.buy {
  background: var(--card);
  border: 2px solid var(--accent);
  border-radius: 6px;
  padding: 1rem 1.2rem;
  margin: 2rem 0;
}

a.button {
  display: inline-block;
  background: var(--accent);
  color: #ffffff;
  padding: 0.7rem 1.2rem;
  border-radius: 4px;
  font-family: Arial, Helvetica, sans-serif;
  font-weight: bold;
  text-decoration: none;
}

a.button:hover {
  background: var(--accent-dark);
}

footer.site {
  margin-top: 3rem;
  padding-top: 1rem;
  padding-bottom: 2rem;
  border-top: 1px solid var(--line);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.85rem;
  color: var(--muted);
}