import { Container } from "https://deno.land/x/postcss@8.4.16/lib/postcss.js";
Passes all declaration values within the container that match pattern through callback, replacing those values with the returned result of callback.
This method is useful if you are using a custom unit or function and need to iterate through all values.
root.replaceValues(/\d+rem/, { fast: 'rem' }, string => {
return 15 * parseInt(string) + 'px'
})