MediaWiki:Common.css

/* CSS placed here will be applied to all skins */
/* Only hide sidebar for anonymous users */
body.skin-vector-2022.logged-out .vector-menu-toggle-button,
body.skin-vector-2022.logged-out .vector-sidebar-container,
body.skin-vector-2022.logged-out #mw-sidebar {
}
body.skin-vector-2022.logged-out #mw-content {
  margin-left: 0 !important;
}