body {
  background-color: #f5f5f5;
  max-width: 960px;
  margin: 0 auto;
  font-family: monospace;
  line-height: 1.5;
  text-align: center;
  height: 100vh;
  overflow: hidden;
}

h1 {
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  margin: 0;
  font-size: large;
}

footer {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 0.75em 0;
  color: #555;
  background-color: #f5f5f5;
}