// BS3 -> BS4 saw a removal of margin-top on headers,
// which is a pretty jarring change, expecially for Rmd
// https://github.com/twbs/bootstrap/blob/f17f882d/dist/css/bootstrap.css#L1219-L1250
// https://github.com/twbs/bootstrap/blob/4de4874e/scss/_reboot.scss#L82-L89

@if $bootstrap-version >= 5 {
  // For BS5+, only apply the margin-top if pandoc's CSS classes
  // are present. This way rmarkdown::html_document_base will continue
  // to have margin-top (which is good), but 'raw' headers won't, which
  // leads to a better experience with accordions, popovers, etc
  // (their design/examples expect headers that don't have margin-top).
  // It also seems as though Quarto docs don't generate these CSS classes,
  // but it also seems they've added their own rules https://github.com/quarto-dev/quarto-cli/blob/0e662c/src/resources/formats/html/bootstrap/_bootstrap-rules.scss#L595-L613.
  // In pandoc, `--to html4` writes `div.section.levelX` and `--to html5`
  // produces `section.levelX` elements.
  .section, section {
    &.level1, &.level2, &.level3 {
      margin-top: 1.5 * $spacer;
    }
    &.level4, &.level5, &.level6 {
      margin-top: $spacer;
    }
  }

} @else {

  h1, h2, h3 { margin-top: 1.5 * $spacer;}
  h4, h5, h6 { margin-top: $spacer; }

}