smuniza1/gist:953d51af9234bc1051ca

## gistfile1.txt
    <style>
        /* Colors */
        body {
             background: url(http://i.imgur.com/aZty7Mq.png);
             animation: mymove 4s linear infinite;
             -webkit-animation: mymove 4s linear infinite;
             -moz-animation: mymove 4s linear infinite;
        }
        @keyframes mymove {
            0% { background-position: 0 0; }
            50% { background-position: 40% 0; }
        }
        #sun {
            position: absolute;
            width: 300px;
            height: 300px;
            top: 20%;
            left: 10%;
        }
        .image {
            background: url(http://i.imgur.com/DGkZYZQ.png);
        }
    </style>

    <html>
    <body>
            <img id="sun" src="http://i.imgur.com/DGkZYZQ.png">
    </body>
    <script src="//code.jquery.com/jquery-1.10.2.js"></script>
    <script src="//code.jquery.com/ui/1.11.4/jquery-ui.js"></script>
    <script>
    var width = 300;
    var sun = $("#sun");

    sun.draggable({
      axis: "x",
      containment: 'body',
      drag: function() {
        var x = sun.offset().left + (sun.width() / 2);
        var total = $(window).width();

        var heightPct = Math.pow((total / 2) - x, 2) / Math.pow($(window).width() / 2, 2);
        console.log(x, $(window).width(), heightPct * 100);
        this.style["margin-top"] = "" + Math.round(heightPct * 30) + "%";
      }
    });
    $("#sun").bind("drag", function(event, ui) {
    var halfWidth = $(window).width() / 2;
    var left = $(this).offset().left + 100;
    var windowWIdth = $(window).width() - 200;
    var image = $('.image');

    $('.position').html(left);
    $('.window').html(windowWIdth);

    if(left < halfWidth) {
        image.css('background-image', url('http://i.imgur.com/f3UFHb7.png'));
    }

    if (left > windowWIdth) {
        image.css('background-image', url('http://i.imgur.com/o7cwLDa.png'));
    }
});
    </script>
    </html>
	<style>
	/* Colors */
	body {
	background: url(http://i.imgur.com/aZty7Mq.png);
	animation: mymove 4s linear infinite;
	-webkit-animation: mymove 4s linear infinite;
	-moz-animation: mymove 4s linear infinite;
	}
	@keyframes mymove {
	0% { background-position: 0 0; }
	50% { background-position: 40% 0; }
	}
	#sun {
	position: absolute;
	width: 300px;
	height: 300px;
	top: 20%;
	left: 10%;
	}
	.image {
	background: url(http://i.imgur.com/DGkZYZQ.png);
	}
	</style>

	<html>
	<body>
	<img id="sun" src="http://i.imgur.com/DGkZYZQ.png">
	</body>
	<script src="//code.jquery.com/jquery-1.10.2.js"></script>
	<script src="//code.jquery.com/ui/1.11.4/jquery-ui.js"></script>
	<script>
	var width = 300;
	var sun = $("#sun");

	sun.draggable({
	axis: "x",
	containment: 'body',
	drag: function() {
	var x = sun.offset().left + (sun.width() / 2);
	var total = $(window).width();

	var heightPct = Math.pow((total / 2) - x, 2) / Math.pow($(window).width() / 2, 2);
	console.log(x, $(window).width(), heightPct * 100);
	this.style["margin-top"] = "" + Math.round(heightPct * 30) + "%";
	}
	});
	$("#sun").bind("drag", function(event, ui) {
	var halfWidth = $(window).width() / 2;
	var left = $(this).offset().left + 100;
	var windowWIdth = $(window).width() - 200;
	var image = $('.image');

	$('.position').html(left);
	$('.window').html(windowWIdth);

	if(left < halfWidth) {
	image.css('background-image', url('http://i.imgur.com/f3UFHb7.png'));
	}

	if (left > windowWIdth) {
	image.css('background-image', url('http://i.imgur.com/o7cwLDa.png'));
	}
	});
	</script>
	</html>