You may need two or more light sensors.
Light is one thing while color is something else.
The light sensors that I know are un-believelable sensitive to light, so they modify consistently and rapidly, leaving your LED light not perceived from this noise.
But in a sense you may use this sensitivity to reach your goal. So, the code will have to detect high changes in the intensity of light.
Then, if you have a pair of sensors, they will detect the changes in one plane. Another pair will detect the changes in the other plane.
This - if you go for a cartesian detection (XYZ). But if you go for an angle positioning, that is a different story, and perhaps more laborious in terms of calculus. Check robotics.
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From my experience, the color sensors are of mixed efficiency, so it may be the case to check the particular one you have.
That is if you go for budget items.
An alternative may be to use the line-follower robots strategy while wearing a white glow with a black strip.
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I suggest starting by detecting one-plane move XY.
You may add Z (height) at a later stage. Or decide for a different positioning system.