body {
  margin: 40px auto;
  max-width: 40em;
  line-height: 1.6;
  font-size: 18px;
  color: #222;
  padding: 0 10px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
}

h1,
h2,
h3,
h4 {
  text-align: center;
}

h2 {
  font-size: 22px;
}

h3 {
  
}