Allows add-ons to easily override the theme, and allows us to apply
styling to elements outside of the normal document flow (like applying
the normal background colour to a position: fixed element).
Anki now solely relies on the night mode setting in the preferences
to decide whether to show in light or dark mode. Some users wanted
to run Anki in light mode while keeping the rest of their system dark,
and there were various display problems when dark mode was changed
after Anki started that couldn't be easily worked around.
NSRequiresAquaAppearance is set again, which means we can rely on
the interface appearing properly and not changing as the macOS theme
is changed.
Users who only use dark mode, and preferred the native look of widgets
in dark mode, can achieve the previous appearance by running the
following command in the terminal:
defaults write net.ankiweb.dtop NSRequiresAquaSystemAppearance -bool no
And the following in the debug console:
mw.pm.meta["dark_mode_widgets"] = True
This is hidden behind a debug console command because it requires the
user ensure their system is always set to the same light/dark mode
as Anki.
Forces the Fusion theme when running night mode, so we don't need
to work around platform themes that don't respond to the defined
palette.
Feedback/suggestions on the chosen colours welcome - _vars.scss is the
file to change if you want to experiment with adjustments.
