#counter {
  text-align: center;
  font-size: 750px;
  margin: 0;
  line-height: 1;
}

#free-space {
  text-align: center;
  font-size: 100px;
}

#counter.full {
  color: red;
  font-size: 350px;
}

#settings {
  position: fixed;
  top: 0;
  background-color: steelblue;
  padding: 10px;
}