The pool, network and interface cards had a solid green or red header
with light text, and status words (Connected, ON, OFF, the DRBD state)
were in the theme's green or red text colour. axe found them below the
WCAG AA 4.5:1 contrast on the live theme (4.29:1, 3.52:1), on the
default zephyr theme, whose green is light (2.5:1), and on dark themes
(darkly 1.18:1).
The card headers, and the status words as badges, are now the theme's
pale status background with its dark status text (bg-*-subtle with
text-*-emphasis). Bootstrap derives the pair from each theme's palette,
and it does not depend on the page's background: the dark Bootswatch
themes keep light-mode emphasis colours, which on their own would be
dark text on a dark page. The card border keeps the status colour.
