chromium/third_party/blink/web_tests/http/tests/css/resources/css-resources-referrer-import.css

@font-face {
    font-family: faceInImportedSheet;
    src: url('referrer-check.php?from=importedSheet&resource=font');
}

.imageInImportedSheet {
    background-image: url('referrer-check.php?from=importedSheet&resource=image');
}
.imageSetInImportedSheet {
    background-image: -webkit-image-set(
        url('referrer-check.php?from=importedSheet&resource=image2') 1x,
        url('referrer-check.php?from=importedSheet&resource=image') 2x
    );
}