IE7 ignores CSS attribute selector only on pages coming from production server

Question

On my website, IE7 seems to be ignoring certain CSS attribute selectors. The strange thing is that it only happens when the page comes from the production server. If I have the

Answer 1

As discussed in the comments, according to this answer by thirtydot and this answer by scunliffe, it seems very likely to be the effect of a security feature in Internet Explorer. Your production server lives within your intranet, and is being accessed via a private, class A IPv4 address (10.*.*.*), which I suspect basically causes IE7 to render pages in quirks mode (and IE8 and newer to render pages in Compatibility View).

All this is just a guess, though, I'm afraid — I haven't been able to reproduce your problem in any IE browser on any system, at least not on your personal server or with my own files. If your production server is open to public access, not just technically, perhaps you could provide a link to it so we can debug further, as the problem is obviously localized to just your production server.