This thread has inspired me to add some new features to Dialog, letting authors specify a color scheme that the web interpreter will apply in reasonable ways. Fill in six shades of lightness fitting your basic palette, then optionally two or four versions of an accent color, and it’ll adapt to dark mode and such automatically.
It’s not much, but it’s better than default white on black (or vice versa)! Previously this would require editing the CSS directly.
EDIT: Speaking of which, if anyone knows a website that can easily produce hex codes for six shades of lightness for the main color (not necessarily monochromatic, but synergistic with each other) and two or four versions of an accent color, do let me know, and I might include a pointer to it. My own color vision is not great so I appreciate tools like that to make sure I’m not putting magenta on top of goldenrod again.