1. First, open the PPT document to be edited, find and select the slide to be set, and right-click the option of setting background format.
2. After the dialog box for setting background format pops up, check the option box for hiding background graphics in the first filling, and click Close.
Be careful not to click Apply All, or the background of all slides will be modified.
3. At this point, you can see that the master background of the selected slide has been removed and turned white.
4. In addition, you can find the background on the right under this tab by clicking the "Design" option in the menu bar, or you can achieve the same effect by selecting Remove Shadow-hidden background graphic.