Either your inverter board or the LCD backlight has failed. Guide to replace the screen is here. You should be able to locate a reasonably priced screen assembly, since a lot of those machines have dead logic boards. I recommend checking eBay.
We have a chance to guarantee our right to repair electronic
equipment—like smartphones, computers, and even farm equipment. This is a once-in-a-generation
chance to protect local repair jobs—the corner mom-and-pop repair shops that
keep getting squeezed out by manufacturers.
Join the cause and tell your state representative to support Right to Repair. Tell them you believe repair should be fair, affordable, and accessible. Stand up for your right to repair!