fix images in docs

Author: v1rtl

docs/introduction.mdx

@@ -15,17 +15,9 @@ straight forward effects-chain.
 npm install @react-three/postprocessing
 ```
 
-<p align="center">
-  <a href="https://pqrpl.csb.app" target="_blank">
-    <img width="274" src="bubbles.jpg" alt="Bubbles" />
-  </a>
-  <a href="https://5jgjz.csb.app" target="_blank">
-    <img width="274" src="control.jpg" alt="Take Control" />
-  </a>
-</p>
-<p align="middle">
-  <i>These demos are real, you can click them! They contain the full code, too. 📦</i>
-</p>
+[![Bubbles](bubbles.jpg)](https://m94xb.csb.app)
+
+[![Control](control.jpg)](https://5jgjz.csb.app)
 
 #### Why postprocessing and not three/examples/jsm/postprocessing?