What an absolutely superb concept. I commend you on not only building out the cool mechanics and gameplay, but also developing an amusing backstory and visuals to go with it. Very nice!
As mentioned by ghost_dad, I think a "grace period" between getting caught would be useful. Say 1 or 2 seconds where you have a chance to hide or get out of the light. Failing that, even just adding a delay and some sound/animation to indicate you've been caught would help make it feel less abrupt.
The music was good, but I think the game could have had more other audio to make it feel more ambient.
The gameplay was great, but I think the difficulty spikes to hard and new mechanics are introduced too quickly. I think that just comes down to time and being able to add more levels to make the progression feel more even.
Overall, really great work!