body {
  margin: 0 auto;
  max-width: 50em;
  font-family: "Helvetica", "Arial", sans-serif;
  line-height: 1.5;
  padding: 4em 1em;
}
h1 {
  margin-top: 1em;
  padding-top: 1em;
}
img {
  margin-top: 1em;
  padding-top: 1em;
  max-width: 50em;
  display: block;
  margin-left: auto;
  margin-right: auto;
}