This is because the background color is set to green and can be modified, which is not caused by the eye protection mode. Please refer to the following steps to modify.

1. First, exclude the eye protection mode setting, because the eye protection mode is turned on in the following states.

2. Click the "Page Layout" option in the menu above WPS software.

3. Then on its menu page, click the "background" option.

4. Then in the drop-down window that appears, select white to click.

5. After completing the above settings, you can turn the background color into white.