@namespace url(http://www.w3.org/1999/xhtml);

html>body>img[src$="png"]:only-child,
html>body>img[src$="PNG"]:only-child,
html>body>img[src$="gif"]:only-child,
html>body>img[src$="GIF"]:only-child {
background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAADBJREFUOE9jPHPmDAM2YGxsjFWcAagBK/iPA4xqQA4unKGESwJXcDOMakAKAaqFEgAimoiVYgl0RQAAAABJRU5ErkJggg==) fixed;
}