Restyle the Slides

## Do you have an eye for design?
Help us improve the look of the slide deck.
If you need help, check out the Appendix in the training manual.

Start by locating the slide deck and reviewing the Appendix in the training manual for project guidance. Compare the current slides as a set, then define completion as a consistent, visibly improved presentation style across the deck.

索引モデルが issue の本文から書いたものです。