https://blog.wongcw.com/2021/11/17/%e6%94%9c%e6%89%8bfragment-design%ef%bc%9abeats-flex%e9%99%90%e9%87%8f%e6%ac%be%e7%84%a1%e7%b7%9a%e8%80%b3%e6%a9%9f%e5%94%ae69-99%e7%be%8e%e5%85%83/