korih,
<!DOCTYPE html>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<style type="text/css">
.hot{
border: 1px dashed Gray; padding: 5px; height: 100px; width: 100px
}
</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script>
<script>
$(function() {
var client;
$("#auth").mousedown(function() {
client = true
});
$("body").mouseup(function() {
client = false
}).mousemove(function(event) {
var clientCoords = event.clientY - $("#auth").height() / 2;
if (client == true) $("#auth").css({
marginTop: clientCoords
})
})
});
</script>
</head>
<body>
<div class="hot" id="auth"></div>
</body>
</html>