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How do i make a div animate diagonally?
<html>
<head>
<meta charset="utf-8">
<link href="style.css" rel="stylesheet"/>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
</head>
<body>
<script type="text/javascript">
$(document).ready(function(){
 $("#box1 div").animate({left: '+=150', top: '+=150'}, 1000);
});
</script>
<div id="box1"></div>
</body>
</html>

#box{
    position: absolute;
}

$("#box1").animate({left: '+=150', top: '+=150'}, 1000);

$("div#box1")   //correct

$("#box1 div")  //incorrect

<div id="box1" style="position:absolute;">s</div>

$("#box1 div").animate({left: '+=150', top: '+=150'}, 1000);

$("#box1").animate({left: '+=150', top: '+=150'}, 1000);