visual design. Change the Position of Overlapping Elements with the z-index Property
Change the Position of Overlapping Elements with the z-index Property When elements are positioned to overlap (i.e. using position: absolute | relative | fixed | sticky), the element coming later in the HTML markup will, by default, appear on the top of the other elements. However, the z-index property can specify the order of how elements are stacked on top of one another. It must be an integer..