Lines lines lines

Hey Apple community,

I have a big issue. I have had vertical lines (of about 3inches usually white, sometimes different neon colours) running down my screen on/off for around a year. And up until a month or so ago, it would usually vanish quickly, but it is now permanently on my screen.

It's in the middle of the screen and when it could disappear I would sometimes be prompted by my closing or opening the lid. But now it won't budge, and in the past day the rest of the screen has now broken - all the screen is neon/flashing blue/green/yellow. Anyone have an idea of what it? And how much it will cost the fix it?

Thanks!