body {
  margin: 0;
  background: #eff5f8;
  color: #20394d;
  font:
    16px/1.7 system-ui,
    sans-serif;
}
main,
header,
footer {
  max-width: 820px;
  margin: auto;
  padding: 24px;
}
header {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}
main {
  background: #fff;
  border: 1px solid #dbe5ec;
  border-radius: 16px;
  padding: 36px;
  box-sizing: border-box;
}
h1 {
  font:
    2.4rem/1.15 Georgia,
    serif;
  max-width: 700px;
}
h2 {
  font-size: 1.2rem;
  margin-top: 2rem;
}
a {
  color: #244cb3;
  text-underline-offset: 3px;
}
nav {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.notice {
  background: #fff3dc;
  border-left: 4px solid #b46c00;
  padding: 14px 18px;
}
.plans {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}
.plan {
  padding: 18px;
  background: #eff5f8;
  border-radius: 10px;
}
.plan h3 {
  margin-top: 0;
}
.price {
  font-size: 1.35rem;
  font-weight: 700;
}
.button {
  display: inline-block;
  padding: 10px 18px;
  border-radius: 7px;
  background: #365edb;
  color: white;
  font-weight: 600;
  text-decoration: none;
}
li {
  margin: 0.4rem 0;
}
.muted {
  font-size: 0.9rem;
  color: #526675;
}
footer {
  font-size: 0.9rem;
}
@media (max-width: 640px) {
  main {
    border-radius: 0;
    padding: 24px;
  }
  h1 {
    font-size: 2rem;
  }
}