ol.chapter li.affix:first-child {
  font-size: 1.5em;
  line-height: 2.2em;
  text-align: center;
  letter-spacing: 0.5px;
}

ol.chapter li strong:first-child {
    margin-right: 2px;
}

ol.chapter li.spacer {
  margin: 8px 0;
}