Transparency and Shadow
opacity: number
The opacity of the entire block along with its content. A number from 0 to 1. Where 0 is full transparency, and 1 is full visibility.

elevation: number (0 - 24)
The height of the shadow. A number from 0 to 24. The shadow is displayed only if the background color of the block is opaque.

shadowColor: Color
The color of the block's shadow. The shadow also requires specifying the shadow height elevation. The shadow is displayed only if the background color of the block is opaque.
