<style>
	.demo_css_sprt, .demo_css_sprt div	{
		background: white;
		border:dotted 1px red;
		padding: 1em;
	}
	.demo_css_sprt div	{
		margin: 1em 0;
	}
	.demo_css_sprt div:not(.nored)	{
		background: mistyrose;
	}
	.demo_css_sprt p	{
		background: white;
		border: dashed 1px blue;
		margin-bottom: 1em;
		padding: 1em;
	}
</style>
<div class="demo_css_sprt">
	要素
	<div>
		要素2
		<div>要素3</div>
		<div class="nored">要素4</div>
	</div>
	<div class="nored">
		要素5
		<p>要素6</p>
		<div>要素7</div>
	</div>
	<div>要素8</div>
</div>