update site

site/404.html

@@ -82,5 +82,16 @@
         </style>
       </div>
     </div>
+    <!-- Global site tag (gtag.js) - Google Analytics -->
+    <script async src="https://www.googletagmanager.com/gtag/js?id=UA-151755889-1"></script>
+    <script>
+      window.dataLayer = window.dataLayer || [];
+      function gtag() {
+        dataLayer.push(arguments);
+      }
+      gtag('js', new Date());
+
+      gtag('config', 'UA-151755889-1');
+    </script>
   </body>
 </html>