css/css-flexbox/flexbox_first-line.html

<!DOCTYPE html>
<title>flexbox | first-line</title>
<link rel="author" href="http://opera.com" title="Opera Software">
<link rel="help" href="http://www.w3.org/TR/css-flexbox-1/#placement">
<link rel="match" href="flexbox_first-line-ref.html">
<style>
ul {
	background: #3366cc;
	padding: 0;
	list-style: none;
	width: 900px;

	display: flex;
	flex-wrap: wrap;
}
li {
	background: #ffcc00;
	margin: 2em;
	border: 1px solid black;
}
ul:first-child::first-line {
	justify-content: space-around;
}
</style>

<ul>
	<li>filler</li>
	<li>Antidisestablishmentarianism</li>
	<li>filler</li>
	<li>Antidisestablishmentarianism</li>
	<li>Antidisestablishmentarianism</li>
	<li>filler</li>
	<li>Antidisestablishmentarianism</li>
	<li>filler</li>
</ul>