Slow CSS Load

This may be a tough one for you guys to see - but hoping you can help.

My site scores pretty well on GTmetrix. But there are CLS issues all over the site as the HTML seems to load a bit before the CSS. This is primarily when landing on any page rather than internal navigation.

Any ideas? I think this only started happening recently. I made some slight optimization changes such as moving scripts to the footer. But nothing I can think of that would affect the CSS load.