Centered heading with rules

dabblet.css

/* Centered heading with rules*/
/*General:*/
h1 {
	position: relative;
	overflow: hidden;
	text-align: center;
	}
h1:before,
h1:after {
	content: "";
	position: relative;
	display: inline-block;
	width: 50%;
	height: 2px;
	vertical-align: middle;
	background: #000;
	}
h1:before {    
	left: -.5em;
	margin-left: -50%;
	}
h1:after {    
	left: .5em;
	margin-right: -50%;
	}
/*Additional*/
h1 {
	/*white-space: nowrap; */
	/*text-overflow: ellipsis;*/
	/*overflow? overflowed header? for what?*/
	font: 1.6em/1.1 Georgia;
	padding: .2em 0;
}
/*Multiline*/
h1>span {
	display: inline-block;
	vertical-align: middle;
	white-space: normal;
	}
/*Works on any background*/
html {
	background: #f06;
	background: linear-gradient(45deg, #f06, yellow);
	min-height: 100%;
	font: 1.3em/1.5 Georgia;
	}

dabblet.html

<h1>Hello!</h1>

<p>Here are the centered headings with horizontal lines.</p>

<p>They are one-lined by default, but if it needs to be multiline, then you can add an extra span.</p>

<h1><span>Multiline heading<br/>with an extra wrapping span</span></h1>

<h1>Some long, long heading without a wrapping span, so it would be overflown. Some long, long heading without a wrapping span, so it would be overflown. Some long, long heading without a wrapping span, so it would be overflown.</h1>

<p>↑ Here you can see one-lined heading, with text-overflow: ellipsis. Since it's too long, the horizontal lines cannot be seen.</p>

settings.json

{"view":"split-vertical","fontsize":"100","seethrough":"","prefixfree":"1","page":"css"}