Edit in JSFiddle

<h1 class="title05">
WEBデザイナーのしおり
</h1>

.title05 {
	position: relative;
	padding: 1em 0;
}
.title05::before,
.title05::after {
	position: absolute;
	left: 0;
	content: '';
	width: 100%;
	height: 6px;
	box-sizing: border-box;
}
.title05::before {
	top: 0;
	border-top: 2px solid #ccc;
	border-bottom: 1px solid #ccc;
}
.title05::after {
	bottom: 0;
	border-top: 1px solid #ccc;
	border-bottom: 2px solid #ccc;
}