Background Image defined in css class after url rewriting

I have successfully rewritten URL but not able to get background images which are defined in stylesheet.css file.
 Im using master page.

 i have used this <link href="<%=ResolveUrl("~/StyleSheet.css") %>" rel="stylesheet" type="text/css" />
but the background image defined in css class file not rendering on page.
Images are defined in .css file are as follows -> background-image: url(image/img_276.jpg);
Plz help.
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