.markdown-section {
  counter-reset: chapter-lv-1; }
  .markdown-section h2 {
    counter-reset: chapter-lv-2; }
    .markdown-section h2:before {
      counter-increment: chapter-lv-1;
      content: counter(chapter-lv-1) ". "; }
  .markdown-section h3 {
    counter-reset: chapter-lv-3; }
    .markdown-section h3:before {
      counter-increment: chapter-lv-2;
      content: counter(chapter-lv-1) "." counter(chapter-lv-2) ". "; }
  .markdown-section h4:before {
    counter-increment: chapter-lv-3;
    content: counter(chapter-lv-1) "." counter(chapter-lv-2) "." counter(chapter-lv-3) ". "; }