Z-index help - CSS

Question

I'm trying to experiment. The instruction/explanation is in the code.
I'm trying to use z-index to display a block on top, but not working.
https://code.sololearn.com/WI44BX288qHk/?ref=app

If question = not understood, let me know.

Answer 1

This story will make you understand...

Listen:
"Jane have sheet of paper and her left hand ... And than, she want to place the sheet of paper between her hand and her palm..."
How would she do???

==> That is the same scenario with your code. A :before is considered as it belongs to the element it's called on.
** The blue div is the sheet
**The red div is the hand
**The green box is the palm

You could easily make it using three div elements that are positioned "non-static"...