  margin: 0;
  padding: 1px 1em;
  border-left: .5em solid #eee;
}
hr, .footnotes::before { border: 1px dashed #ddd; }
.frontmatter { text-align: center; }
#TOC {
  a { text-decoration: none; }
  ul { list-style: none; padding-left: 1em; }
  & > ul { padding: 0; }
  ul ul { border-left: 1px solid lightsteelblue; }
}
.body h2 { border-bottom: 1px solid #666; }
.body .appendix, .appendix ~ h2 { border-bottom-style: dashed; }
.main-number::after { content: "."; }
span[class^="ref-number-"] { font-weight: bold;