Always increase Z- index in animations

Hi all, I have built this interaction and while hovering one of the five text blocks the image in the background changes. Unfortunately this effect only goes once, because after doing it, the image with the highest Z index is on top. However, I would like to have it so that I can do it infinitely often. However, the image should not automatically disappear, but be replaced by the next one.

Here is my public share link: [LINK][1]
([how to access public share link][2])

[1]: Webflow - Website)
[2]: Share a read-only link | Webflow University