Diablo classic when launched only takes up a small corner of my screen. How do i make it so the game screen fills up my monitor?

Things i've tried that didn't work:
Changing display mode to same as desktop and scaling method to integer then copying ddraw.dll, dxcfg.exe and dxcfg.ini from the diablo/dx folder to the diablo folder

set destop resolution lowest than native. open video driver control panel - set scaling to "Keep Aspect Ratio". Change desktop res back if you want.
google it for add info and even screens.