CSS custom properties polyfill for ie11

Question

Is there a way to pollyfill a custom CSS property for ie11 with JavaScript? I was thinking on load, check if browser supports custom properties and if not do some kind of find a

Answer 1

The Webcomponents library has polyfills that (among other things) provide custom property/CSS variables support to IE11. Note that the whole library is quite much, since it also polyfills custom HTML elements, HTML imports and shadow DOM.

https://www.webcomponents.org/polyfills

https://github.com/WebComponents/webcomponentsjs