diff --git a/index.html b/index.html
index e8d5daa..2039f51 100644
--- a/index.html
+++ b/index.html
@@ -5,6 +5,23 @@
     <link rel="manifest" href="https://lax18.github.io/WebStrayer/manifest.json">
     <link rel="stylesheet" type="text/css" href="style.css">
     <link rel="icon" type="image/png" href="https://i.imgur.com/O4AeOvI.png">
+    <script>
+  if ('serviceWorker' in navigator) {
+  window.addEventListener('load', function() {
+  navigator.serviceWorker.register('service-worker.js').then(function(registration) {
+  // Registration was successful
+  console.log('Registered!');
+  }, function(err) {
+  // registration failed :(
+  console.log('ServiceWorker registration failed: ', err);
+  }).catch(function(err) {
+  console.log(err);
+  });
+  });
+  } else {
+  console.log('service worker is not supported');
+  }
+  </script>
   </head>
   <body onload="changePDF('chapter 1');onLoad();">
     <table width="100%" height="100%">
