body {
  max-width: 40em;
  margin: 0 auto;
  padding: 15px;
  font-family: Georgia, serif;
  font-size: 18px;
  line-height: 1.6em;
  color: black;
}

h1, h2, h3 {
  font-family: sans-serif;
  font-weight: normal;
  line-height: 1em;
}

#footer {
  margin-top: 50px;
}

div {
  margin: 25px auto;
}

img {
  width: 100%;
}