Normally our documents are black text over white background. If you do extensive reading on your smartphone, tablet, or computer, PDF Reader supports to change the default background color of PDF files for an eye-friendly reading environment.
1. Open one PDF
2. Tap the "Viewer Mode" button on the left side of the screen
3. Choose the background theme from the color panel. Currently, PDF Reader provides 3 themes for you to choose from, including the day, sepia, and night mode
4. Then the background color will be automatically changed