Why did I get a black screen from nowhere

I was just playing on my pc and wanted to look at smth on my phone so i tried to turn it on but it has a black screen. The phone still works because it still vibrates and can use a flashlight cuz i have a double click shortcut for that and that also works. I tried using tutorials on how to restart a phone with a black screen and i did just that, the screen did turn on but only like dark gray color was on the screen. It is like the black color screens make that is not actually black so that was it. And my question is what to do to fix that issue or what happened to it.