If you're writing with a program that allows you to change the color of the paper, change it to a mint green, like so:

Compared to white, staring at a mint green screen is more soothing and less taxing on the eyes, and your eyes won't hurt after staring at the screen for too long.

Whenever I'm working on Microsoft Word, I always do this because I used to get headaches and migraines from staring at the screen without taking a break. With the paper a mint green color, I can write for longer without risking another headache.

Also, if your writing program allows you to, such as Word, zoom in as much as you can so that you don't see the white margins anymore.

Hope this helps somebody like it did me!