body {
  font-family: Arial, sans-serif;
  margin: 0;
}

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

h1 {
  margin: 0;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

nav ul li {
  display: inline-block;
  margin-right: 1rem;
}

nav ul li a {
  color: #fff;
  text-decoration: none;
}

main {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  padding: 1rem;
}

section {
  flex-basis: 30%;
}

h2 {
  margin-top: 0;
}

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

ul li {
  margin-bottom: 0.5rem;
}

ul li a {
  color: #333;
  text-decoration: none;
}