gsgleason,
I'd suggests overriding fonts as done
here. That code is literally "overriding fonts".
Other than that, note that "particular CSS changes nothing" doesn't necessarily mean, that it is not supported. Another explanation is: book has CSS that is more "specific", i.e. has
higher priority.
If the book has css that looks like, say:
Code:
p.article {
line-height: 100%;
}
it would override your body {...} statement.
PS
Reminder: in PRS+ 2.0.x , you have to open different book, then get back to original book to actually apply new css.