Update demo link and preview image in README

Author: Fellmonkey

.media/preview.png

@@ -1,14 +1,14 @@
 
 **You can view the demo in your browser:**
-👉 [Open the Unity WebGL Playground Demo](http://localhost:8000)
+👉 [Open the Unity WebGL Playground Demo](https://fellmonkey.github.io/playground-appwrite-unity/)
 
 # Appwrite's Unity Playground 🎮
 
 This Unity project is a simple way to explore the Appwrite API with the Appwrite C# SDK in Unity. Use it to learn how to integrate Appwrite into a Unity app and try common features end‑to‑end.
 
 The main sample script lives at `Assets/Scripts/AppwriteUnityPlayground.cs` and wires up UI buttons to SDK calls (Auth, Databases, Storage, Functions, Teams, Locale, Realtime).
 
-![Appwrite Playground](preview.png)
+![Appwrite Playground](.media/preview.png)
 
 ## Get Started