1 item (1 fix)
A text element's line box measures max(declared line-height, the font's own natural box), so a column of rows built to a browser mockup's arithmetic runs long and overflows its fixed parent. Padding, borders, margins and gaps all measure exactly as declared: only the line box inflates. Size rows off the font size, not off an assumed 1.5×, and verify on a scale-1 capture.
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