Drill 29: Improve it — Spacing and sizing

* {
  box-sizing: border-box;
}

.card {
  width: 100%;
  max-width: 40rem;
  padding: 1.5rem;
  margin: 2rem auto;
}

.card h2 {
  margin-top: 0;
  font-size: 1.5rem;
}

.badge {
  font-size: 0.75em;
  padding: 0.5em 1em;
}