want to make a divA with div1.div2, div1 and div2 the same size content is the same, but div2 has color, I just want to move the mouse into the divA area and use transition to make the original transform scale (0 (0) div2 into transform scale (1) 1) so as to realize the central magnification and display of colored div2, for a long time, many methods have encountered a lot of problems have not been successful, I think we have to use js to achieve it.