The art style is done very well and goes well with the dark theme. Perhaps try using more contrasting colours to show the difference between light and dark more instead of it being all dark/neutral tones. An example could be turning the enemies into 'bad glowing light'.
The game mechanics and gameplay is fun and has a clear objective to reach the end and find the light on the way.
You could add in a task box to show how many lamps you have lit up/how many are left.