body {
  font-family: Arial, sans-serif;
  background-color: #f5f5f5;
  color: #333;
  text-align: center;
}

header, footer {
  background-color: #333;
  color: #fff;
  padding: 1em;
}

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

nav li {
  display: inline-block;
  margin: 0 1em;
}

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

a:hover {
  color: #555;
}

main {
  padding: 2em;
}