@-moz-document url-prefix(http://www.google.com/reader), url-prefix(https://www.google.com/reader), url-prefix(http://google.com/reader), url-prefix(https://google.com/reader) {

.item-body img, 
.item-body a img, 
.item-body embed { 
    max-width:100% !important; 
    height: auto !important; }

}