body {
  font-family: sans-serif;
  margin: 0;
  background: #f0f0f0;
}

header {
  background: #333;
  color: #fff;
  padding: 1rem;
}

nav a {
  color: #fff;
  margin-right: 1rem;
  text-decoration: none;
}

main {
  padding: 2rem;
  background: #fff;
  margin: 1rem;
  border-radius: 8px;
}

footer {
  text-align: center;
  padding: 1rem;
  background: #333;
  color: #fff;
}