URLs
CSS Ref HTML Ref
Uniform Resource Identifiers
A URL value is given by url(foo), where foo is the URL. The URL may be optionally quoted with either single (') or double (") quotes and may contain whitespace before or after the (optionally quoted) URL.
Parentheses, commas, spaces, single quotes, or double quotes in the URL must be escaped with a backslash. Partial URLs are interpreted relative to the style sheet source, not to the HTML source.
Examples:
BODY { background: url(stripe.gif) }
BODY { background: url(http://www.htmlhelp.com/stripe.gif) }
BODY { background: url( stripe.gif ) }
BODY { background: url("stripe.gif") }
BODY { background: url(\"Ulalume\".png) } /* quotes in URL escaped */