Tutorials (schueltke):

 - repaired links to tutorial
 - reverted change in commit 66623ac1

docs/index.md

@@ -41,7 +41,7 @@ Learn how to set it up & install the prerequisites.
 
 Design your first aircraft.
 
-[:octicons-arrow-right-24: Tutorials](tutorials/standalone.mp4)
+[:octicons-arrow-right-24: Tutorials](tutorials/changing-design-specifications.md)
 </div>
 
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