[llvm] [llvm-cov] Add HTML dark theme support (PR #93080)

[via llvm-commits]

EdJoPaTo wrote:

Ah yeah, I confused myself there with the font color. I haven't touched cyan in my PR but yeah, looks like that can be improved too.

I'm not entirely sure what the meaning of the cyan marking is or where it might be relevant. Haven't seen it from Rust (which is where I use this) so far I think. (Mainly out of curiosity as "cyan" isn't really a speaking name)

I ran your example and used the updated styles manually (having an older version installed which doesn't have this yet).
Changing the background-color to `#0ff6` for cyan seems to work. The accessibility tool in Firefox is happy about its contrast in both light and dark theme. Sadly it's not as clear in the dark theme but having it more obvious also results in less contrast. And for now the basic approach is to have as little theme specifics as possible, so I wouldn't override the font color only for this one.

I can do a follow-up PR. You could also change that. Not really important to me who improves this.

https://github.com/llvm/llvm-project/pull/93080