it seems it is not implemented in S7:I have (translated from french) settings/display/ but not the advanced option. eventually I can go to livedisplay where I find color profile/display mode/color temperature and a sadvanced option color calibration. However non of them allow dark style I can just reduce color temperature to be less “blue”
I think the dark mode is under Oreo. For the moment, the /e/ official build for S7 is still Nougat…
I had a Leeco S2 and it’s only with an unofficial build under Oreo that the “advanced option” and “dark mode” appear.