> the C64 could display a total of 16 colors at a standard resolution of 120 x 200 pixels, though it also has a graphics mode with the higher resolution of 320 x 200 with more limited colors

I'm not sure where your 120 pixels are coming from, looks like an error. Color mode was half the resolution of the hires mode (2 hires pixels were taken together to represent 4 values that a color pixel could represent; there were 40x25 blocks (corresponding to characters in text mode) where the colors used for each of the 2 or 4 states could be set (with some additional complication as it was using a separate RAM chip for part of that, the details of which escape my memory without looking it up). There were also 8 sprites of 24 (hires) or 12 (color) pixels horizontally, those don't add up to 120 pixels either.