Why do all the windows in the room have to be pasted with black paper and hung with ultraviolet curtains? It may have something to do with feng shui. Solve?

In addition to the problem that the room will be troubled by the sun exposure in the west, the windows of the room will be pasted with black paper and ultraviolet curtains will be hung. If the windows of other normal rooms are covered with black paper and ultraviolet curtains, the room will be too full of geomantic omen because of opacity, which is very unfavorable. Unless someone wants to accumulate Yin Qi in the room, it is beneficial for them to communicate with some ghosts.