In IE10 (browser and document mode both IE10, no compat view) on Windows 7 x64, the web application I'm developing, looks ok. When I open the IE10 developer tools, the styling (CSS) gets completely broken.
Issue is also described on the links below:
When I process all CSS files through the (Yahoo) YUI compressor, into a minified all.css, the problem doesn't occur. After some analysis, I saw that when I split one specific (1921 lines) CSS file into 2 files, the problem is gone. This is far below the 4095-rules limit (which is something different than a line limit).