如何让jQuery从最后一个位置设置动画到新位置?

$("a#pack1").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '8px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "0px"}, 1000);
				});
				$("a#pack2").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '52px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-590px"}, 1000);
				});
				$("a#pack3").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '95px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-1150px"}, 1000);
				});
				$("a#pack4").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '138px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-1740px"}, 1000);
				});
				$("a#pack5").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '181px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-2397"}, 1000);
				});
				$("a#pack6").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '224px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-3064px"}, 1000);
				});
				$("a#pack7").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '268px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-3700px"}, 1000);
				});
				$("a#pack8").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '311px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-4256px"}, 1000);
				});
				$("a#pack9").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '350px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-4885px"}, 1000); //medical surveillance
				});
				$("a#pack10").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '394px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-5495px"}, 1000); //scheduler
				});
				$("a#pack11").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '438px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-6110px"},1000); //rehab reminder
				});
				$("a#pack12").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '480px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-6720px"}, 1000); //cost
				});
				$("a#pack13").click(function (){
					$('#solutions').animate({
						'background-position-x': '9px',
						'background-position-y': '525px'
					},1000,'linear');
					$('#content-data').animate({marginTop: "-7324px"}, 1000); //legal
				});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="solutions">
		<ul>
				<li><a id="pack1" href="javascript:void(0);">Leave</a></li>
					<li><a id="pack2" href="javascript:void(0);">Job Links</a></li>
					<li><a id="pack3" href="javascript:void(0);">Non Work Related</a></li>
					<li><a id="pack4" href="javascript:void(0);">Work Related</a></li>

					<li><a id="pack5" href="javascript:void(0);">Safety</a></li>
					<li><a id="pack6" href="javascript:void(0);">Ergonomics</a></li>
					<li><a id="pack7" href="javascript:void(0);">Industrial Hygiene</a></li>

					<li><a id="pack8" href="javascript:void(0);">Medical</a></li>
					<li><a id="pack9" href="javascript:void(0);">Medical Surveillance</a></li>
					<li><a id="pack10" href="javascript:void(0);">Scheduler</a></li>
					<li><a id="pack11" href="javascript:void(0);">Rehab Reminder</a></li>
					<li><a id="pack12" href="javascript:void(0);">Cost</a></li>
					<li><a id="pack13" href="javascript:void(0);">Legal</a></li>
			</ul>
	</div>