I'm using this kit for my blog with very minimal styling (basically list-style and a single bg-color).

Most of the time it looks correct.

But under some conditions the contrast of text/background goes to almost zero (notice the invisible titles?)

I can get this to happen by toggling the "night mode" option on Firefox iOS. Some others have reported it in a variety of conditions that I cannot reproduce.

What's going on here? Is this from styling in deno_blog or gfm? I can't find anything that would do this, but its consistent.