Update index.md

Author: streamcode9

index.md

@@ -32,14 +32,15 @@ Earth
 
 Universe and Everything
 * [Science](/2024/01/02/science.html)
-* [Ukulele](/2024/07/12/ukulele.html)
-* [Music theory](/2024/11/05/music-theory.html)
-* [Music](/2024/07/02/music.html)
-* [Literature](/2024/06/30/literature.html)
-* [Art](/2024/07/03/art.html)
-* [Games](/2024/01/01/games.html)
-* [Cinema](/2024/01/05/cinema.html)
-* [Origami](/2024/07/01/origami.html)
+* Culture
+  * [Music](/2024/07/02/music.html)
+    * [Music theory](/2024/11/05/music-theory.html)
+    * [Ukulele](/2024/07/12/ukulele.html)
+  * [Art](/2024/07/03/art.html)
+    * [Origami](/2024/07/01/origami.html)
+    * [Games](/2024/01/01/games.html)
+    * [Cinema](/2024/01/05/cinema.html)
+  * [Literature](/2024/06/30/literature.html) 
 
 ---