UIKit datepicker not working correctly with modal window?

Question

JavaScript

UIKit is connected to the site, this framework has a datepicker and modal windows.
The problem is that the datepciker is inserted into the body, which means that if you call the calendar inside a modal, that calendar behaves like it's position:fixed; , and does not remain attached to the input when scrolling.

I am attaching a link. It is necessary that the modal scrolls, the calendar stays in place, and does not scroll along with the screen
https://codepen.io/SkuvaWeb/full/NBXvvo/