Tricky element positioning exercise.

This was a good one for exploring element layering and absolute positioning. Again, 95% done in under 2 hours, but the final positioning puzzles required me to go back and rethink things, trying options. I did the styling changes for the section open/close in a pretty verbose way in JS. I'm sure I also could have done this by just updating a class on the section parent and making the changes in my css file, but I wanted the practice with JS DOM traversing. Any feedback or suggestions are always welcome!