I use the Cloudfare CDN for both domain.

This is my serviceWorker.js

/* Service worker */ 
const cacheName = "alessandro-tarparelli-site-v1"
const filesToCache = [
  "/test/PWA/",
  "/test/PWA/manifest.json",
  "https://cdn-ajjt.it/resources/static/css/main.css",
  "https://cdn-ajjt.it/resources/static/css/responsive.css",
]


self.addEventListener('install', event => {
  event.waitUntil(
    caches.open(cacheName)
      .then(cache => {
        console.log('Opened cache');
        return cache.addAll(filesToCache);
      })
  );
});

self.addEventListener('fetch', event => {
  event.respondWith(
    caches.match(event.request)
      .then(response => {
        if (response) {
          return response;
        }
        return fetch(event.request);
      })
  );
})

When I load the page the files doesn’t cache on cache storage