Trying to check for figcaption height and if 100% scroll down to 10%

figcaption.css

figure {
	margin: 100px auto;
	width: 479px;
	height: 541px;
	overflow: hidden;
	position: relative;
}

figcaption {
	position: absolute;	display: block;
	width: 479px;
	height: 50px;
	left: 0px;
	bottom: 0px;
	text-align: center;
	color: #fff;
	background-color: rgba(255,255,255,.8);
	line-height: 50px;
	
	transition: bottom 0.2s;
}
figcaption h3 {
	font-size: 34px;
	color: #ae1e22;
	font-family: 'Antic', sans-serif;
	padding-top: 5px;
}
figure:hover figcaption {
	bottom: 0px;
	height:100%;
}

figcaption.js

<script>
		var $figcaption = $("figcaption");
		var fullHeight = $("figure:hover figcaption").css('height');
		function checkForHeight() {
			if ($figcaption.css('height') = fullHeight ) {
	    		$('figure:hover figcaption').animate({ height:'10%' }, 500);
	    	}
		}
	});
</script>