:root {
  font-family:
    system-ui,
    -apple-system,
    "Microsoft YaHei",
    sans-serif;
  color: #223e37;
  background: #f7f9f7;
  line-height: 1.8;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
}
a {
  color: #176b55;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
header,
main,
footer {
  max-width: 1100px;
  margin: auto;
  padding: 24px;
}
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid #dbe6df;
}
header nav {
  display: flex;
  gap: 28px;
}
.brand {
  font-size: 21px;
  font-weight: 700;
}
main {
  padding-top: 60px;
  min-height: 70vh;
}
h1 {
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.4;
  margin: 12px 0 22px;
}
h2 {
  line-height: 1.5;
}
.eyebrow {
  color: #658477;
  font-size: 13px;
  letter-spacing: 2px;
}
.summary {
  color: #64766d;
  font-size: 18px;
  max-width: 800px;
}
.cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 40px;
}
.card {
  background: #fff;
  border: 1px solid #e2e9e4;
  border-radius: 12px;
  padding: 28px;
  color: inherit;
}
.card:hover {
  border-color: #64a48d;
  text-decoration: none;
}
.card span,
.card p {
  color: #78867f;
}
.card h2 {
  font-size: 22px;
}
.card b {
  color: #176b55;
  font-size: 14px;
}
article {
  max-width: 800px;
  margin: 28px auto;
}
.body {
  font-size: 17px;
  margin: 40px 0;
  overflow-wrap: anywhere;
}
.body p {
  margin: 22px 0;
}
.body h2 {
  margin-top: 40px;
}
aside {
  border-top: 1px solid #dbe6df;
  padding-top: 18px;
  font-size: 14px;
  overflow-wrap: anywhere;
}
aside h2 {
  font-size: 17px;
}
.pages {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-top: 40px;
}
footer {
  border-top: 1px solid #dbe6df;
  color: #7f8e85;
  font-size: 13px;
  margin-top: 40px;
}
@media (max-width: 640px) {
  header {
    display: block;
  }
  header nav {
    margin-top: 12px;
  }
  main {
    padding-top: 32px;
  }
  .cards {
    grid-template-columns: 1fr;
  }
  header,
  main,
  footer {
    padding-left: 20px;
    padding-right: 20px;
  }
}