body {
  font-family: Arial, sans-serif;
  text-align: center;
  background: #f2f4f8;
  margin: 0;
}
header nav ul {
  list-style: none;
  padding: 0;
  background: #004aad;
  margin: 0;
  display: flex;
  justify-content: center;
}
header nav ul li {
  margin: 0 20px;
}
header nav ul li a {
  color: white;
  text-decoration: none;
  font-weight: bold;
}