Chap05 -> Handling routes not found

QandA/frontend/src/App.tsx

@@ -9,6 +9,7 @@ import { fontFamily, fontSize, gray2 } from './Styles';
 import { AskPage } from './AskPage';
 import { SearchPage } from './SearchPage';
 import { SignInPage } from './SignInPage';
+import { NotFoundPage } from './NotFoundPage';
 
 function App() {
   return (
@@ -25,6 +26,7 @@ function App() {
           <Route path="search" element={<SearchPage />} />
           <Route path="ask" element={<AskPage />} />
           <Route path="signin" element={<SignInPage />} />
+          <Route path="*" element={<NotFoundPage />} />
         </Routes>
       </div>
     </BrowserRouter>

QandA/frontend/src/NotFoundPage.tsx

@@ -0,0 +1,4 @@
+import React from 'react';
+import { Page } from './Page';
+
+export const NotFoundPage = () => <Page title="Page Not Found">{null}</Page>;