fix(css): fix the issue #8, according to the changes from the forked source.

[wangziling]

1. fix(css): fix the issue #8, according to the changes from the forked source.

2. chore(layout): enable to automatically set dark theme-color Enhance the dark mode layout on the IOS devices, make the status bar more comfortable and smoother. 尽量让IOS手机上状态栏和页面同色。（因为背景色是 radial-gradient 的，所以截图里并不是完全同色）。 电脑深色模式时，PWA标题栏 上颜色变深。 这俩颜色都来源于本项目源码。