body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
}
header, footer {
  background: #000;
  color: #fff;
  padding: 1rem;
}
nav ul {
  list-style: none;
  padding: 0;
}
nav ul li {
  display: inline;
  margin-right: 1rem;
}