Non-matching colors between Python and JavaScript

URL of experiment: FR_online_free [PsychoPy]

Description of the problem: I am currently attempting to run a color singleton experiment online. In short, participants are presented with 8 shapes (1 is different from the rest), and their goal is to report the location of a dot in the one shape that is different from the rest. In example, lets say there are 7 diamonds and 1 circle, their goal would be to attend to the circle and report the location of a dot in the circle. The picture below might help explain.

In this case, the target would be the circle, and the subject would indicate that the dot is on the right side. The issue I am running into is when I move the experiment online. An example of the issue can be seen in the photo below.

On a given trial, in order to show only one dot at a time, one of the dots in each shape is chosen randomly and is made black while the other is made the same color of the shape that it is in so that it blends in and cannot be seen. As you can see, this does not seem to be working in the online version. The grey circles, the grey dots in those circles, and they grey diamond are all assigned the same hex value, but they appear as distinct. I tried using both hex value assignments and string color words, but neither has worked. The dots in these circles should not be visible, to be clear.

I can provide further information for clarification if needed. Any help is appreciated.