This question would be best asked at your terrible web designers.
Unfortunately since you gave none of the requested information when asking a question it is hard to say what could be the issue. I will however take a stab at some generic help. What you want to do is at least narrow down where the issue is, the website, a windows issue, a hardware / software issue. I would start with disabling Hardware Acceleration in your browser. You can google how to do this. If this does help, verify that the same thing happens across multiple browsers, ie, firefox, chrome, edge etc... This will tell you if it is you or them. If it's you, you now have to figure out if it's a Windows update issue or Driver issue. Make sure you have all Windows Updates installed and Clean Install the latest graphics driver. Not even knowing, what graphics you have, I can't suggest an avenue as to how to do that. I hope you have checked already if you have this issue on other computers?