develop report styles based on non-system fonts

as mentioned in #1420

we should not use system fonts b/c they look nicer on macs than other platforms, and if we use system fonts, those of us on macs will not see what a big chunk of users see, and will therefore have a mistaken impression of how good things look and how the various fonts and spacings fit togetehr. We should design to one consistent standard, and use a non-system webfont for cases where zilla slab is not appropriate

Start by reading the referenced issue #1420 and the report styling guidance in this issue. Determine which non-system font and spacing standard should replace platform-dependent fonts, then verify that report styles render consistently across platforms.

Written by the indexing model from the issue text.