Why the right indentation appears after adding a min-height?

When you add a minimum height to the unit, it appears at a certain width of the right margin, who can explain to me why is this happening?
With a given height of the gray block:
5a7176e7c3732689091586.jpeg

Without a specified height all safely stretches.
June 8th 19 at 17:25
1 answer
June 8th 19 at 17:27
example

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