Update index.html

Author: JumperOnJava

spin/index.html

@@ -13,7 +13,7 @@
     <!-- <span id="dbg">123</span> -->
     <br>
     <br>
-    <a href="spin/" style="font-size: 20px; font-family: 'Comic Sans MS', 'Comic Sans', cursive;">iOS native version <br>with background playback<br>(source code)</a>
+    <a href="https://github.com/JumperOnJava/spintrick" style="font-size: 20px; font-family: 'Comic Sans MS', 'Comic Sans', cursive;">iOS native version <br>with background playback<br>(source code)</a>
     <br>
     <br>
     <video controls src="vid.mp4" id="vid" width="300"></video>