first commit

sw.js

@@ -0,0 +1,23 @@
+const CACHE_NAME = 'qr-code-pwa-v1';
+const assetsToCache = [
+    '/',
+    '/index.html',
+    '/style.css',
+    '/script.js',
+    'https://cdn.jsdelivr.net/npm/tailwindcss@2.2.19/dist/tailwind.min.css',
+    'https://cdnjs.cloudflare.com/ajax/libs/qrcode-generator/1.4.4/qrcode.min.js'
+];
+
+self.addEventListener('install', event => {
+    event.waitUntil(
+        caches.open(CACHE_NAME)
+            .then(cache => cache.addAll(assetsToCache))
+    );
+});
+
+self.addEventListener('fetch', event => {
+    event.respondWith(
+        caches.match(event.request)
+            .then(response => response || fetch(event.request))
+    );
+});