Well, for the phone, start using the built in blue light filter and download something like "night shift" from play store for additional even darker screen when using at night. Main point is making the blue spectrum lesser. For the pc, hoping u are on windows, search "gamma" and something like "calibrate the screen" comes up. Go through that calibrate your screen. And once u get to the step where there are 3 adjustment for red, green and blue color, decrease the blue to a comfortable level. Also keep the "Night light" feature always on. This works for me, experiment for yourself based on this.