Why doesn't height:100% of an element follow the height of its parent that has a max-height value set? Width works just fine.

A minor annoyance, but an annoyance anyhow.

a web page is just a cutted piece of an endless role of paper

Honestly I feel bad for anyone that needs to use CSS on a daily basis, i have to use it now and again, and it just feels so limiting and awkward, sites these days are full screen, why is that not the default state of CSS, also you have variables for CSS now using :root, why can't these variables be used the calc, etc also why can't you set a variable to the height of a element... Like having to mix JavaScript in to do these simple things is so annoying, I wish you could do web dev like android and allow elements to be anchored to other elements, views to fill_parent, etc. CSS makes everything so much more work that it should be in 2018...