Betta_Fish

[Feature Request] Add China AQI Index

1

Open Meteo currently supports the AQI index in the US/Europe, which is very good I hope that [China AQI Index](https://en.wikipedia.org/wiki/Air_quality_index#Mainland_China) can be added in the future to provide consistent services...

**Is your feature request related to a problem? Please describe.** 目前，白天和夜晚时使用相同背景（仅根据天气更改）。 **Describe the solution you'd like** 支持在夜晚时切换到不同背景。 自定义背景时，在文件名后加上"_night"即可。

### Description I would like to add Open Meteo API support to my UWP weather application Unfortunately, UWP only supports .NET Standard 2.0 ### Describe the solution you'd like Change...