W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<head>
<style>
#DIV1 {
  height: 200px;
  width: 200px;
  margin: auto;
  border: 1px solid black;
}

#DIV2 {
  width: 150px;
  height: 150px;
  border: 1px solid black;
  background-color: coral;
  transform: rotate(45deg);
}

#DIV2original {
  position: absolute;
  width: 150px;
  height: 150px;
  border: 1px dashed grey;
  background-color: lightgrey;
  opacity: 0.5;
}
</style>
</head>
<body>

<p>Click the "Try it" button to set the origin of the rotation to 0 for both the x-axis and the y-axis:</p>

<p><b>Note: </b>The grey DIV element indicates where the DIV2 element would be without the transformation.</p>

</body>
</html>