查看“MediaWiki:Common.css”的源代码

/* CSS placed here will be applied to all skins */
#ca-varlang-0 {
    display: none !important;
}

.treeview {
	margin-top: 0.3em;
	display: flow-root;
}

.treeview .treeview-header {
	padding-left: 3px;
	font-weight: bold;
}
.treeview .treeview-header:last-child {
	border-color: #636363 !important;
	border-left-style: dotted;
}
.treeview .treeview-header:not(:last-child)::before {
	content: none;
}
.treeview .treeview-header:last-child::before {
	border-bottom: 0;
}

.treeview ul,
.treeview li {
	margin: 0;
	padding: 0;
	list-style-type: none;
	list-style-image: none;
}

.treeview li li {
	position: relative;
	padding-left: 13px;
	margin-left: 7px;
	border-left: 1px solid #636363;
}
.treeview li li::before {
	content: "";
	position: absolute;
	top: 0;
	left: -1px;
	width: 11px;
	height: 11px;
	border-bottom: 1px solid #636363;
}

.treeview li li:last-child:not(.treeview-continue) {
	border-color: transparent;
}
.treeview li li:last-child:not(.treeview-continue)::before {
	border-left: 1px solid #636363;
	width: 10px;
}

.treeview dl,
.treeview dt {
	margin-bottom: 0;
}