5.3 Corner Clipping

Chapter 5 - Rounded Corners - 5.3 Corner Clipping

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border-radius-clipping
Border radius clipping
When set with 'overflow: hidden', outer container should clip background of an element insides at the corners.
border-radius-overflow-hidden
Clipping to the border-radius curve
Effects that clip to the border or padding edge (such as 'overflow' other than 'visible') must clip to the curve