The first commented line is your dabblet’s title

dabblet.css

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

span {
  background: #f00;
}

span[c] { background: green; }

div {
  	height: 100px;
	background: #ff0;
	font-size: 24px;
	outline: 1px solid;
}

div span {

}

*{cursor:default}

dabblet.html

<span a>Short</span><span b>Some much longer span</span><span c>Short</span>
<br/><br/><br/><br/><br/>
<div>
  <span d>Short</span><span e>Some much longer span</span><span f>Short</span>
</div>
<div>
  baseline<span e>Some much longer span</span>
</div>

dabblet.js

// alert('Hello world!');

settings.json

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