<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:nth-last-of-type(2)  {
		background: mistyrose;
	}
	.demo_css_sprt p	{
		background: white;
		border:dashed 1px blue;
		padding: 1em;
	}
</style>
<div class="demo_css_sprt demo">
	要素
	<div>
		要素
		<div>要素</div>
		<div>要素</div>
		<div>要素</div>
		<div>要素</div>
	</div>
	<div>
		要素
		<p>要素</p>
		<div>要素</div>
		<p>要素</p>
		<div>要素</div>
		<p>要素</p>
	</div>
	<div>要素</div>
</div>