How to interact with blocks that are under the canvas?

Question

css

Good afternoon.
canvac is drawn on top of another block. If you make the z-index of the canvas greater than that of the block below it, then it is displayed correctly and everything that is drawn on it is visible. But you can't interact with the block below. And if you make the z-index smaller than that of the block below it, then the canvas stops drawing correctly (it is covered by a block with a large z-index), but you can interact with the block below it.
Tell me how to draw the canvas on top of everything, but when you click on the blocks below it, interact with them, and not with the canvas?