diff --git a/apps/demo/index.html b/apps/demo/index.html
index ee5ba6390..803d6eb52 100644
--- a/apps/demo/index.html
+++ b/apps/demo/index.html
@@ -1,15 +1,41 @@
 <!DOCTYPE html>
 <html lang="en">
-  <head>
-    <meta charset="UTF-8" />
-    <link rel="icon" type="image/svg+xml" href="/favicon.ico" />
-    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <meta name="theme-color" media="(prefers-color-scheme: light)" content="<%- themeColorLight %>">
-    <meta name="theme-color" media="(prefers-color-scheme: dark)" content="<%- themeColorDark %>">
-    <title><%- title %></title>
-  </head>
-  <body>
-    <div id="root"></div>
-    <script type="module" src="/src/main.tsx"></script>
-  </body>
-</html>
+
+<head>
+  <meta charset="UTF-8" />
+  <link rel="icon" type="image/svg+xml" href="/favicon.ico" />
+  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+  <meta name="theme-color" media="(prefers-color-scheme: light)" content="<%- themeColorLight %>">
+  <meta name="theme-color" media="(prefers-color-scheme: dark)" content="<%- themeColorDark %>">
+  <title><%- title %></title>
+  <script type="text/javascript">
+    // Single Page Apps for GitHub Pages
+    // https://github.com/rafgraph/spa-github-pages
+    // Copyright (c) 2016 Rafael Pedicini, licensed under the MIT License
+    // ----------------------------------------------------------------------
+    // This script checks to see if a redirect is present in the query string
+    // and converts it back into the correct url and adds it to the
+    // browser's history using window.history.replaceState(...),
+    // which won't cause the browser to attempt to load the new url.
+    // When the single page app is loaded further down in this file,
+    // the correct url will be waiting in the browser's history for
+    // the single page app to route accordingly.
+    (function (l) {
+      if (l.search[1] === '/') {
+        var decoded = l.search.slice(1).split('&').map(function (s) {
+          return s.replace(/~and~/g, '&')
+        }).join('?');
+        window.history.replaceState(null, null,
+          l.pathname.slice(0, -1) + decoded + l.hash
+        );
+      }
+    }(window.location))
+  </script>
+</head>
+
+<body>
+  <div id="root"></div>
+  <script type="module" src="/src/main.tsx"></script>
+</body>
+
+</html>
\ No newline at end of file
diff --git a/apps/demo/public/404.html b/apps/demo/public/404.html
new file mode 100644
index 000000000..5ec4dd19f
--- /dev/null
+++ b/apps/demo/public/404.html
@@ -0,0 +1,45 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+  <meta charset="utf-8">
+  <title>Single Page Apps for GitHub Pages</title>
+  <script type="text/javascript">
+    // Single Page Apps for GitHub Pages
+    // https://github.com/rafgraph/spa-github-pages
+    // Copyright (c) 2016 Rafael Pedicini, licensed under the MIT License
+    // ----------------------------------------------------------------------
+    // This script takes the current url and converts the path and query
+    // string into just a query string, and then redirects the browser
+    // to the new url with a query string and hash fragment,
+    // e.g. http://www.foo.com/bar/baz becomes http://www.foo.com/?p=/bar/baz
+    //
+    // If you're creating a Project Pages site and NOT using a custom domain,
+    // then set segmentCount to 1 (enterprise users may need to set it to > 1).
+    // This way the code will only replace the route part of the path, and not
+    // the real directory in which the app resides, for example:
+    // https://username.github.io/repo-name/one/two?a=b&c=d#qwe becomes
+    // https://username.github.io/repo-name/?p=/one/two&q=a=b~and~c=d&h=qwe
+    // Otherwise, leave segmentCount as 0.
+    var segmentCount = 0;
+
+    var l = window.location;
+    // If we are on GitHub Pages (project site), segmentCount should be 1
+    if (l.hostname.indexOf('github.io') > -1) {
+      segmentCount = 1;
+    }
+
+    l.replace(
+      l.protocol + '//' + l.hostname + (l.port ? ':' + l.port : '') +
+      l.pathname.split('/').slice(0, 1 + segmentCount).join('/') + '/?/' +
+      l.pathname.slice(1).split('/').slice(segmentCount).join('/').replace(/&/g, '~and~') +
+      (l.search ? '&q=' + l.search.slice(1).replace(/&/g, '~and~') : '') +
+      l.hash
+    );
+  </script>
+</head>
+
+<body>
+</body>
+
+</html>
\ No newline at end of file
