Request to remove inner-shadow filter

[rkloth]

Is your feature request related to a problem? Please describe.
There is a hard definition of an inner shadow which cannot be removed or configured. I would argue that it shouldn't be present if the component is supposed to be somewhat unopinionated. The developer should however have some means of styling the masked sections (?)

Describe the solution you'd like
My suggestion would be to remove the inner shadow filter or make it configurable.

Additional context
Add any other context or screenshots about the feature request here.

Resulting in: