CSS Nested border-radius

You've probably set the parent and child element border-radius to the same value expecting them to line up, but it's the padding that throws the angle of the curve off

The inner radius needs to equal the outer radius - padding

.parent{
	padding: 1.25rem;
	border-radius: 3rem;
}

.child{
	border-radius: 1.75rem;
}

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