css landing page

client/public/index.html

@@ -3,15 +3,26 @@
 
 <head>
   <meta charset="UTF-8" />
-  <title>Lean 4 Game</title>
+  <title>Lean Game Server</title>
+  <style>
+    body {
+      font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
+    }
+  </style>
 </head>
 
 <body>
   <div id="root"></div>
   <noscript>
-    You need to enable JavaScript to run this app.
+    <div class="landing-page">
+      <h1>Lean Game Server</h1>
+      <p>
+        <i>You need to enable JavaScript to use the Lean Game Server, as it is built
+        using React.</i>
+      </p>
+    </div>
   </noscript>
   <script src="bundle.js"></script>
 </body>
 
-</html>
+</html>