Cool project! But I must say, the algorithm that computes the percentage score seems rather poor, at least if the goal is to score the percent visual difference

Cool project! But I must say, the algorithm that computes the percentage score seems rather poor, at least if the goal is to score the percent visual difference between the selected color and the actual. It gave me 100% on Coca-Cola (and I replicated the 100% with a slightly different shade in a different browser tab), yet I got only 3.14% for leaving Apple the default color, which looks almost the same as the correct color. Some of my other answers were similarly penalized heavily for brightness being a little off even if the hue was almost exact. The visual difference between those colors and the correct colors was far less than the visual difference between some of my higher scoring answers and the correct color.