Don't have any suggestions yet, because the site comes up fine for me right now.
Yesterday when you posted, the HTML document returned by index.php was the only thing that came through. (Which created a visual result similar to you were describing.) Every single resource the page had tried to load (.css sheets, .js scripts) was being denied as 404 / does not exist.
But when I tried to capture a LAN trace and dig deeper, suddenly the site was offline entirely, saying a connection couldn't be made to the IP address at all. So I assumed your host must be in the middle of restarting or testing something in response to your ticket, and left it alone.
Re-testing just now shows the site up as expected, and all resources loading successfully. Is it still failing for you, or do you know there are reports that the site is still failing?