#function-url-quotes

Require or disallow quotes for urls.

a { background: url("x.jpg") }
/**                 ↑     ↑
 *             These quotes */

#Options

string: "always"|"never"

#"always"

Urls must always be quoted.

The following patterns are considered warnings:

@import url(foo.css);
@document domain(http://www.w3.org/);
@font-face { font-family: 'foo'; src: url(foo.ttf); }
@-moz-document url-prefix() {}

The following patterns are not considered warnings:

a { background: url('x.jpg'); }
@import url("foo.css");
@document domain('http://www.w3.org/');
@font-face { font-family: "foo"; src: url("foo.ttf"); }
@-moz-document url-prefix('') {}

#"never"

Urls must never be quoted.

The following patterns are considered warnings:

a { background: url('x.jpg'); }
@import url("foo.css");
@font-face { font-family: "foo"; src: url('foo.ttf'); }

The following patterns are not considered warnings:

a { background: url(x.jpg); }
@import url(foo.css);
@font-face { font-family: 'foo'; src: url(foo.ttf); }

#Optional secondary options

#except: ["empty"]

Reverse the primary option if the function has no arguments.

For example, with "always".

The following pattern is not considered warnings:

@-moz-document url-prefix() {}