Two percentage traps
Level 12 of 13Your goal
Give the 300px-wide .parent a height of 200px. Then make .child fill it exactly (outer size 300 × 200) with padding: 10% on every side. That is 30px, because percentage padding uses the parent's width. Keep the padding inside that size.
Must use
heightElements
Hover one to find it on the stage. Click it, or put your cursor inside its CSS rule, to focus on just that element.
marginborderpaddingcontenttarget content boxtarget outer edge (green = matched, red = not yet)your element (hovered or focused)
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