CSS 网页适配 iPhoneX

1、<meta name="viewport" content="width=device-width, viewport-fit=cover">
2、body

body {
  padding-bottom: constant(safe-area-inset-bottom);
  padding-bottom: env(safe-area-inset-bottom);
}
3、fixed bottom=0

{
  padding-bottom: constant(safe-area-inset-bottom);
  padding-bottom: env(safe-area-inset-bottom);
}
或者

{
  height: calc(60px(假设值) + constant(safe-area-inset-bottom));
  height: calc(60px(假设值) + env(safe-area-inset-bottom));
}

参考：https://blog.csdn.net/chunxiaqiudong5/article/details/104065563