gecko/toolkit/themes/gnomestripe/global/notification.css

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

notification {
  background-color: InfoBackground;
  color: InfoText;
}

notification[type="info"] {
  background-color: -moz-Dialog;
  color: -moz-DialogText;
}

notification[type="critical"] {
  background-color: red;
  color: white;
}

.messageImage {
  width: 16px;
  height: 16px;
  margin: 0px 1px 0px 6px;
}

.messageText {
  -moz-margin-start: 5px;
}

.messageButton {
  margin: 0px 5px 0px 5px;
}

.messageCloseButton {
  list-style-image: url("moz-icon://stock/gtk-close?size=menu");
}