Brett on 10 Oct, 2018 03:01 PM
It doesn't export all of the CSS, but a base "export" section of it.
Most custom styles don't account for all of the baseline styling, just
what they need to modify on top of it, so including the base is the only
way to ensure that the output page looks as expected based on the
preview. In your case, I think manually linking the CSS file is the best
option, but I'm willing to consider a "custom css only" option in the
export panel in the future.