https://blog.wongcw.com/2020/10/27/mac%e7%ab%afpowerpoint%e6%9b%b4%e6%96%b0%ef%bc%9a%e5%8f%af%e6%8f%92%e5%85%a5%e9%8c%84%e9%9f%b3%e6%94%af%e6%8c%81%e5%b0%8e%e5%87%ba%e7%82%bagif%e5%8b%95%e5%9c%96/