header {
  text-align: center;
}

#instructions {
  padding: 1em;
}

.instructions {
  display: none;
  /* Inconsistent with rest of content */
  font-family: sans-serif;
  font-weight: bold;
  font-size: 1.25em;
  line-height: 1.5;
  padding: 2em;
  background-color: silver;
  border: 2px solid black;
  border-radius: 1em;
}