How to change z-index of an element in Elementor
In Elementor, you can specify the stack order of an element which is called z-index.
As you know, an element with greater z-index will be above an element with a lower z-index.

In order to assign z-index number to an element in Elementor:
1. In Elementor, select the element to which you want to assign z-index, so that a new dashboard on the left will emerge with the element’s settings.
2. In Advanced tab, and from the Advanced section, type in the z-index number in the Z-index field.
3. Update the page.