The first commented line is your dabblet’s title

dabblet.css

/**
 * The first commented line is your dabblet’s title
 */

h1 span{
	color:Red  /* I only target <span> tags nested within a h1 */
}

h1 ~ span{
	color:blue /* I dont taget <span> tags nest within a h1, but any <span> tag that follows a h1 on the same nested level */
}

dabblet.html

<!-- 
	The H1, span and h3, are all siblings
	The spans within the h1, and h3, and descendants of their parent tags
-->
<h1>
	<span>I am a descendant because I am nested within the h1</span>
</h1>

<span> I am a sibling, because I am at the same nested level as the h1</span>

<h3>
	<span> I am not a sibiling of the h1, but I am a decedant of the h3</span>
</h3>

settings.json

{"view":"split","fontsize":"100","seethrough":"","prefixfree":"1","page":"all"}