body {
  width: 45em;
  padding-left: 3em;
}

ol.lectures {
  counter-reset: lecture;
  list-style-type: none;
  margin-left: 2em;
}

li.lecture {
  margin-bottom: 0.5em;
}

li.lecture:before {
  counter-increment: lecture;
  content: counter(lecture) ". ";
  margin-left: -2em;
}

li.cancellation {
  list-style-type: none;
  counter-increment: none;
  color: #888;
  margin-left: -2em;
  margin-bottom: 0.5em;
}