<div id="shot" style="background-color:#2ab9cc;width:10px;height:10px;margin-top:400px;"></div>
<script type="text/javascript">
$(function () {
let x = 0;
let y = 400;
setInterval(function () {
x = x + 1;
// y = y + 1;
console.log(x);
console.log(y);
$('#shot').offset({
top: y,
left: x
});
}, 10);
});
</script>