Is there a way to stop the box from knocking out a box-shadow?

Even with a transparent background, typically a box-shadow doesn't fill the contents of a box.

I think I have seen a demo where this w开发者_Python百科asn’t the case, but can’t recall how it was done. Does anyone know more about this?

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I am having decent success simulating this by setting two box-shadows: one traditional box shadow, and the second inset with a very large spread value.

The suggestion to set the box’s background is also a good one, if you can match it up well.