叠置盒体的局部外挑

提示词

让叠置的矩形盒体在本次选定层局部向外挑出，区分前后实体、外挑底面和下方空隙；仅在选定部位发生进退，不把所有楼层等量平移或画成边界熔合的折块。

Let selected portions of stacked rectangular box volumes project outward at the chosen levels, distinguishing front and rear solids, projecting undersides and the voids below. Limit offsets to the selected areas instead of shifting every floor equally or merging their boundaries into an indistinct folded mass.