body {
  max-width: 80em;
  margin-left: auto;
  margin-right: auto;
}

body header img {
  max-height: 20em;
  max-width: 100%;
}

body header {
  text-align: center;
}

body section article img {
  max-height: 24em;
  float: left;
  border-radius: 10%;
  margin: 1em;
}

body section {
  clear: both;
  float: left;
}


body footer {
  clear: both;
  text-align: center;
}

body footer img {
  max-width: 100%;
}