html {
  background: Teal
}

body {
  background: White;
  min-width: 640px;
  max-width: 100vh;

  margin: 1rem auto;
  border: 1px solid black;
  padding: 1rem
}

header, footer, figcaption, .center {
  text-align: center
}

.large {
  display: inline-block;
  font-size: 250%
}

.flip {
  transform: scaleX(-1)
}

code {
  background: LightGray;
  padding: 0.125rem;
}

table {
  width: 100%;
}

td, th {
  padding: 0.25rem;
  border: 1px solid LightGray
}

th.heading {
  color: White;
  background: Navy
}