For anyone saying that there are scripts, I know about that but its not like they are good, some of them can hurt your eyes.
I want Codeforces itself to do the dark theme and we can switch through the profile settings. That would be really cool and would help during nights or early mornings.
Here is one of the scripts I dowloaded and you can see how bad it is
/predownloaded/76/71/76715e05951c4481894729690e534fc369cdad34.png