code: func readStyle(runes []rune, defaultStyle Style) Style {
  	style := defaultStyle
  	split := strings.Split(string(runes), tokenItemSeparator)
  	for _, item := range split {
  		pair := strings.Split(item, tokenValueSeparator)
  		if len(pair) == 2 {
  			switch pair[0] {
  			case tokenFg:
  				style.Fg = StyleParserColorMap[pair[1]]
  			case tokenBg:
  				style.Bg = StyleParserColorMap[pair[1]]
  			case tokenModifier:
  				style.Modifier = modifierMap[pair[1]]
  			}
  		}
  	}
  	return style
  }
docs: // readStyle translates an []rune like `fg:red,mod:bold,bg:white` to a style