How can the button in VisionOS development detect the eyes focusing on the button?

VisionOS developers want to modify the color of the button when they detect the eyes focusing on it. May I ask if there are any relevant methods that can be implemented? At present, there is a default highlight color when the eyes focus on the button, but this color is too dim. Not obvious enough, how can I modify it? thank you!

How can the button in VisionOS development detect the eyes focusing on the button?
 
 
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