z-index

Question

can any one explain z-indez for me

Answer 1

The z-index property specifies the stack order of an element.

An element with greater stack order is always in front of an element with a lower stack order.

Note: z-index only works on positioned elements (position:absolute, position:relative, or position:fixed).

Answer 2

https://www.w3schools.com/cssref/pr_pos_z-index.asp