On all browsers I have (chrome firefox and internet explorer) when I try to sign into my google+ linked youtube account youtube will fail to load the style sheet. I can use youtube signed in on mobile or if I am not signed in. this happened on chrome and I couldn't fix it so I went over to firefox where it worked fine for a month and then I clicked on a video and suddenly the style sheet was broken. Youtube is the only site affected.
I have tried clearing cookies and catch, restarting my computer, disabling all add ons and extensions, clearing my computer of any viruses and using a cleaner tool, restarting in safe mode everything short of attempting to make a new stylesheet (going into firefox style editor says the style sheet can not be loaded) all to no avail. please help this is very frustrating.
here is what I am seeing: