I have a Samsung Chromebook that is about a year old and has a 12" screen. I see no actual model number anywhere.....just Samsung and Chrome listed on the top. It's been fine until this weekend. It'd been several months since I had shut it down, but we traveled last weekend and when I started it up everything looked fine until I opened the Chrome browser and when I opened a web site things that should be light were dark and things that should be dark were light. I had a black background and white text where normally it was white background with black text. Then I found that a few web sites looked normal. I left it on all night playing YouTUbe sleep audio and the next morning the video looked relatively normal. I shut it down and that evening it was back to mostly inverted color. I tried switching on High Contrast Mode, but it was no help. Any ideas??