As I revive my interest in astronomy I visit a lot of sites about the sky, stars and planets. Unsurprisingly these sites are often made by hobbyists who favour pale text on a background of starry black. Moreover the text is often small, cramped and generally impossible to read.
Opera though has always championed accessibility. It’s incredibly easy to transform sites such as the one in the first screenshot. Go to the View menu and choose Style > Accessibility layout. Ah: larger black text on a soothing pale green background. Nice.