Microsoft's Advice to Web Developers: Use WP7 Specific CSS
Microsoft this week offered some advice to web developers who are working on mobile versions of their websites: use Windows Phone 7-specific CSS files!
Although Microsoft includes its own Internet Explorer web browser with Windows Phone 7 (WP7), the browser doesn't support CSS3 Media Queries. That's why the Redmond company says that developers will need to use conditional statements to select an appropriate CSS file in order for websites to display correctly on WP7 mobile devices.
This week Microsoft made a statement that is likely to irk many developers, announcing that "The browser team's primary goal in the initial release of Windows Phone 7 was to ensure that any site designed for Internet Explorer would render correctly on Windows Phone 7."