The idea
clip-path cuts an element down to a shape without changing its box — the element still occupies its full rectangle, but only the clipped region is painted. circle(50% at 50% 50%) clips to a circle whose radius is 50% of the box, centred in the middle.
Make the box a 200×200 square and clip it to a circle.
This level needs clip-path — that is the whole point of it.