<!--
The only real caveat to this solution that I’ve encountered so far is the styling limitations present with elements using display: table-row.
Often padding, margin, etc. don’t behave as expected. This is easy enough to work around by adding a <div> or something inside the .page-row and styling that:
-->

<header class="page-row">
	<!-- apply your styles to me -->
	<div class="header-inner">
		<h1>Site Title</h1>
	</div>
</header>