Template:Container/styles.css

.container-header {
	position: relative;
	margin: 0 25px 0 25px;
	overflow: visible;
	border: none;
}

.container-header::after {
	content: "";
	display: block;
	position: absolute;
	left: 0;
	right: 0;
	top: 0;
	bottom: 0;
	width: 100%;
	height: 100%;
	background: #0fd;
	transform: skew(-20deg);
}

.container-header-inner {
	position: relative;
	z-index: 1;
	line-height: 40px;
	text-align: center;
	font-family: sans-serif;
}