Problem Explanation：
Mi Air Purifier has two buttons, which are located on the top and the back respectively:
1. The two functions of the top button are switch and mode switch.
2. During operation, click to switch mode, and long press to shut down.
3. Mi Air Purifier has three operation modes:
Automatic: automatic switching operation mode according to real-time indoor air quality;
Sleep: Operate with ultra-low noise to create a comfortable sleeping environment;
High speed: full speed operation, quick purification.
4. There is an indicator light to show the air quality in the current environment.
5. There is a button on the back to control the light switch (click) and reset the filter element (long press for 6 seconds).
Mi Air Purifier has two buttons, which are located on the top and the back respectively:
1. The two functions of the top button are switch and mode switch.
2. During operation, click to switch mode, and long press to shut down.
3. Mi Air Purifier has three operation modes:
Automatic: automatic switching operation mode according to real-time indoor air quality;
Sleep: Operate with ultra-low noise to create a comfortable sleeping environment;
High speed: full speed operation, quick purification.
4. There is an indicator light to show the air quality in the current environment.
5. There is a button on the back to control the light switch (click) and reset the filter element (long press for 6 seconds).