ol {
  counter-reset: item;
  list-style-type: none;
}

ol > li {
  counter-increment: item;
  position: relative;
}

ol > li:before {
  content: counter(item) ". ";
  font-weight: bold;
  position: absolute;
  left: -1.5em;
}

ol ol {
  counter-reset: subitem;
  list-style-type: none;
}

ol ol > li {
  counter-increment: subitem;
  position: relative;
}

ol ol > li:before {
  content: counter(item) "." counter(subitem) ". ";
  font-weight: normal;
  position: absolute;
  left: -2em;
}

ol ol ol {
  counter-reset: subsubitem;
  list-style-type: none;
  padding-left: 2.5em;
}

ol ol ol > li {
  counter-increment: subsubitem;
  position: relative;
}

ol ol ol > li:before {
  content: counter(item) "." counter(subitem) "." counter(subsubitem) ". ";
  font-weight: normal;
  position: absolute;
  left: -3em;
}