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

@-moz-document domain("youtube.com") {
  #watch-headline-container:not(:hover),
  #masthead-container:not(:hover) {
    background-image: -moz-linear-gradient(top, rgba(255,255,255,.25), rgba(0,0,0,.1))  !important;
    max-height:       1ex;
    overflow:         hidden;
  }
  #masthead-container:not(:hover) {
    background-image: -moz-linear-gradient(bottom, rgba(255,255,255,.25), rgba(0,0,0,.1))  !important;
  }
}