This one feels like it could work, if not for the fact that the tiles used for the plat form is the same as the one used for the bottom floor. I could use different tiles to solve this problem however.
Here’s a crude example edit. All I did was apply a layer of dark blue, set the blend mode to multiply with a 24% opacity. Just darkening a spot on the ground will provide a visual cue that this patch of ground is at a different angle from the rest of the floor.