Accent Color Change Won’t Stick

I’ve seen this question posted in other threads and I’ve tried the answers given in those threats, but they don’t fix the problem. Whenever I try to change the accent color and publish it, it always goes back to the default blue. I tried the custom CSS listed as a workaround, but that did not work either: :root {
–colorPrimary: #ffffff;
}

The site is smithwakelyelectric.com

(see attached screenshot)