How to make a simple modal window in HTML + CSS (without JS)?

Question

css

I'm currently using popup maker. But for my purposes, these are their sparrow guns.
100% transparent background
0 window transparency
hung on the menu item on click (via a specific class?)
width 95% of the screen width
padding from the top edge of the screen 50px
height automatically according to the content
vertical scoring if the content does not fit on one screen
, php code must be executed inside
close button (top right)
Thank you!

Answer 1

take it and make it right

Answer 2

Look here , it seems to me, the simplest css implementations are collected.
But in general, can you imagine how crutches it is and what kind of infernal hell all this is to support?
Get familiar with WP, look at YouTube for manuals on connecting JS. And if you need to do something more serious modals?