2. Next, in the main interface of Xiaomi Sports, click the "My" tab in the lower right corner.
3. In the opened My Page, click the "mi band 3" menu item in the "My Device List".
4. Next, you will open the setting page of mi band 3 and find the menu item "Night Mode" in the page.
5. The night mode setting page of mi band 3 will open. Click the switch behind "Night Mode".
6. In the pop-up menu of setting night mode, you can select the opening time of night mode. When night mode is turned on, the screen of mi band will be dimmed.