body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  text-align: center;
}

header {
  background-color: #4caf50;
  color: white;
  padding: 20px;
}

main {
  padding: 20px;
}

.links a {
  display: inline-block;
  margin: 10px;
  padding: 10px 20px;
  background-color: #4caf50;
  color: white;
  text-decoration: none;
  border-radius: 5px;
}

.links a:hover {
  background-color: #45a049;
}