html {
  background-color: lightgrey;
}
body {
  max-width: 400px;
  margin: 100px auto 100px auto;
  padding: 50px;
  border: 1px solid black;
  border-radius: 40px;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 24px;
  background-color: whitesmoke;
}