Bottom 1/5 of screen occasionally turns black and then purple

So suddenly today a portion of the bottom of the screen started to fade to black and then would end with red and purple lines. After not using my phone for a bit it clears up and seems to go away but eventually comes back, first as gray horizontal lines to the red and purple ones on a black background. The touch screen still works and responds if I touch where the glitch seems to happen, it's just the display that glitches out. It wasn't dropped before this started happening and this came out of nowhere as I was using my phone. I tried to restore my phone to see if it was a software problem but to no avail.