CCS 3 will offer this feature, but it is still not a cross browser, and you cannot do it using traditional HTML + CSS ... for now.
Sites with a tilted image do this by rotating it, say, in Photoshop and making its background transparent. That's the whole trick with her.
Tip. save this picture to your HD and see for yourself. This is probably just a square of the image with a transparent background, or maybe it has a current background that is well suited for placement.
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