Can there be a dark mode style added to the site? Idk about many others, but I've got everything - from my desktop theme to Twitter etc - set to Dark Mode, and it's fast becoming the norm to have both a light and dark mode - which is very nice for those of us who just cannot bear bright white blaring backgrounds.
But please do not make it compulsory, there are some places that choose dark mode with no way of going back to light mode and with my visual processing disorder it is just too difficult to read in dark mode for me. I also dislike things being too bright. One thing that I do and I do not know if it could help the OP is to reduce both brightness and contrast. As a bonus it extends battery life.
I'm pretty sure that the theme we use (called UI/X) has a dark mode option. I'm not certain whether we can seamlessly make it an option without making a bunch of modifications. At some point in the not-too-distant future, we're going to need to do a major upgrade to the forum software we are currently using, as the current version is no longer supported by the manufacturer. When that happens, it absolutely makes sense to offer a dark mode in addition to the current mode. So one way or another, it will likely happen eventually. Whether it can be done soon just requires someone to pay attention to it and see what's involved. We're spread pretty thin right now but this isn't the first request, so it's something we should look at.
On my iOS devices I can choose “Smart Inverse” (in accessibility options) and have the forum with black background and white text. It’s not perfect (for instance, Chip’s cat avatar has glowing white eyes. Do you have such an option? That might be a temporary way of getting close to what you want while reading on EC.