CSS z-index not working (position absolute)

Question

I am trying to make the black div (relative) above the second yellow one (absolute). The black div's parent has a position absolute, too.

#relative {
	position: relative;
	width: 40px;
	height: 100px;
	background: #000;
	z-index: 1;
	margin-top: 30px;
}
.absolute {
	position: absolute;
	top: 0; left: 0;
	width: 200px;
	height: 50px;
	background: yellow;
	z-index: 0;
}

<div class="absolute">
    <div id="relative"></div>
</div>
<div class="absolute" style="top: 54px"></div>

Expected Result:

Answer 1

Remove

z-index:0;

from .absolute.

Updated fiddle here.