As it exists today, Chrome’s dark mode for the web is not ready, as there’s only one option for darkening which sometimes makes pages illegible. With the “cross-platform” version of the flag, Google is offering five prospective dark modes to choose from.
simple HSL-based inversion
simple CIELAB-based inversion
selective image inversion
selective inversion of non-image elements
selective inversion of everything
chrome://flags/#enable-force-dark
some more chrome flags that are handy
for android chrome users
#enable-android-web-contents-dark-mode
will turn web pages dark by default