MediaWiki:Common.css

/* CSS placed here will be applied to all skins */
.res-img img {
	max-width:100vw;
	height:auto;
}

.gallery {
	margin: 0 !important;
}

@media (max-width: 576px) { /*"xxx" the width of window*/
  .thumb  {
    width:100vw !important;
  }
}