MediaWiki:Common.css

/* CSS placed here will be applied to all skins */
body {
  background-image: url('/skins/Vector/resources/images/wiki_header_3.jpg');
  background-repeat: no-repeat;
  background-size: 100%;
  background-color: #121320;
}
#mw-page-base {
  background-image: none;
  background-color: transparent;
}
.notLatestMsg {
  display: none;
}
.approvedAndLatestMsg {
  display: none;
}