update notes about what i learned

Author: LindsayElia

02 - JS and CSS Clock/index-START.html

@@ -125,6 +125,8 @@
       - Adding and removing the transition property is best done by creating a new class
       just for the transitions and adding/removing that class. When I tried to re-apply a
       transition duration, it did not kick back in.
+      https://blog.alexmaccaw.com/css-transitions
+      https://www.bennadel.com/blog/2461-understanding-css-transitions-and-class-timing.htm
   */
   </script>
 </body>