[charleski]

@page {
  margin-top: 9pt;
  margin-bottom: 1pt
}

body {
  font-size: 100%; 
  line-height: 1.25em; /* just a bit more leading than the standard of 1.2 because I read at small sizes. I sometimes bump the font up to 105% too so that the smallest size is easier on my presbyopic eyes */
  margin: 0 12pt;
}

p.flushbrk {  /* the class for the initial paragraph of a section */
  margin-top: 1.25em;
  margin-bottom: 0;
  text-indent: 0
}

p. indent { /* the class for standard indented paragraphs */
  margin: 0;
  text-indent: 1em
}

p. centerbrk { /* for scene-break markers such as asterisks */
  margin: 1.25em 0;
  text-align: center
}

div.extract { /* a div that wraps around paragraphs that are further indented (e.g. verse, letters, etc) */
  margin: 0.625em 2em;
  text-align: left
}
/* often there will be different variations of extract, some with both left and right indents, some with just a left indent, some using a different font, etc */

All formatting is done in the css - I strip out line-spacing garbage (trailing <br/>s and empty p or div tags) using regexes.

All vertical margins are related to the line-height (either a simple fraction or integral multiple) and margins using fractions of the line-height are organised so that the top and bottom add up to a multiple, eg for a subhead I might use

p.subhead {
  margin-top: 1.875em;
  margin-bottom: 0.625em;
  font-style: italic
}

so that the total spacing retains the rhythm of the surrounding body text but the subhead is shifted towards the text to which it relates.