Proof of concept code to show how to work around the iOS Safari Action Bar making 100vh be off the screen.
This code adds two CSS variables:
--iOS-vh-fix--vh: the height of the viewport, minus the height of the Safari action bar and the footer.--iOS-vh-fix--chrome-height: the height of the Safari action and footer.
The example shows how you can use the variables inside a stylesheet (see the CSS comments).
More detailed blog post to come.