I just checked on this. Your display choices in the app are limited to light, dark and sepia. It would be nice if you could enter custom styles for display, but I don’t see that option. That might be an interesting feature to contribute—it’s FOSS!
As far as styling the converted output, it depends. You can style HTML
with CSS
. Pandoc has options to style other formats with custom templates.
The viol instrument family are frettless! Pick up a violin/viola/cello/bass and have fun :)