Apply useful CSS one-liners that fit current site usage

[samsonjs]

Summary

• add line-height: 1.5 on body for improved baseline readability
• add text-wrap: balance for headings to avoid awkward wraps
• add article p { max-width: 65ch; } to keep paragraph measure readable
• intentionally skip table/form/motion one-liners that are not currently used by the main generated site

Verification

• rbenv exec bundle exec bake lint
• rbenv exec bundle exec bake test
• rbenv exec bundle exec bake debug

Closes #31

[samsonjs]

Not sure about the max column width, seems a bit low to me.