I've never seen Nocturne but on Windows 10 inverted colors+night shift works well (IIRC has an option for grayscale, too). On Linux you can achieve the same ef

I've never seen Nocturne but on Windows 10 inverted colors+night shift works well (IIRC has an option for grayscale, too). On Linux you can achieve the same effect with xca+redshift (not sure about grayscale).