I've literally just thought of this (and I'm gutted I completely forgot to mention this in the 2020 survey a few weeks back). But I'm just putting it out there for a 'dark theme' for the website.
My settings across all websites/apps (instagram/facebook/twitter/reddit, etc) are in 'dark mode' so the background is black instead of white. So I'm browsing through all these and then click onto FitnessBlender and I feel like I've just been blinded by all the white background, haha.
Just wondered if this could be an option considered? :) My eyes would definitely appreciate it on the nighttime.