The frame is able to instantly reduce your room.

Mirrors — they are able to increase the room, while visually expanding the walls. You can also completely decorate all the walls with mirrors or use mirror tiles, the main thing is that they are not framed by various frames. The frame is able to instantly reduce your room. If, still, I still want to embellish the shelves with bright objects, then let them be located in the farthest corners, so they extend the trajectory of your gaze, visually increasing the space.