add build-sw.js

docs/index.html

@@ -77,15 +77,22 @@
                 /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
             )
         );
-        var _hmt = _hmt || [];
-        (function () {
-            if (!isLocalhost) {
-                var hm = document.createElement('script');
-                hm.src = 'https://hm.baidu.com/hm.js?b6c9b8bafbf5fe7225160101dafbbc7d';
-                var s = document.getElementsByTagName('script')[0];
-                s.parentNode.insertBefore(hm, s);
-            }
-        })();
+    </script>
+    <script>
+        if (!isLocalhost) {
+            var _hmt = _hmt || [];
+            var hm = document.createElement('script');
+            hm.src = 'https://hm.baidu.com/hm.js?b6c9b8bafbf5fe7225160101dafbbc7d';
+            var s = document.getElementsByTagName('script')[0];
+            s.parentNode.insertBefore(hm, s);
+        }
+    </script>
+    <script>
+        if (!isLocalhost && 'serviceWorker' in navigator) {
+            window.addEventListener('load', function () {
+                navigator.serviceWorker.register('./sw.js');
+            });
+        }
     </script>
 </body>