message: add margin bottom to theme link
diff: @@ -68,6 +68,7 @@ const SideNav = ({router}) => (
  color="gray.9"
  href="/components/docs/primer-theme"
  m={0}
  + mb={4}
  fontWeight={router.pathname === '/components/docs/primer-theme' ? 'bold' : null}
  >
  Primer Theme
  