The same content in each: a heading, a paragraph with inline mathematics in
it, a display equation, and a block of Agda. Every colour, size and face
comes from docs/stylesheets/tokens.css, so what is below is what
the site would look like, not an impression of it. Contrast ratios under each
swatch are computed against that specimen's own background. Dark first,
because that is the site's default. Meridian is the one currently shipping;
Constellation is the agda-algebras documentation site's palette and display
face, with three values adjusted to clear AA — see the comment at the top of
its block in tokens.css.