Modal does not cover page when page is scrolled

[codeithuman]

After opening the modal, you can scroll down the page:

Here is the css you need to fix it:

[codeithuman]

You may also need to add overflow: scroll;. When the validation errors appear it may push the submit button off the screen.

[danielberkompas]

Unfortunately it's not quite that simple, because iPhone 6 screens and smaller require the modal to be scrollable, and overflow: scroll doesn't work for that, apparently.

I switched to a hybrid system: position: fixed on desktop and position: absolute on mobile.