<!DOCTYPE html>
<title>Reference</title>
<style>
div {
  margin: 0;
  position: absolute;
}

#target {
  width: 300px;
  height: 300px;
  top: 0;
  left: 200px;
  background-color: green;
}
</style>

<div>
  <div id="target"></div>
</div>