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<!DOCTYPE html>
<html>
<head>
<style> 
#parentDIV{
  width: 100%;
  height: 300px;
  margin: 10px 0;
  position: relative;
  border: solid black 1px;
}
#myDIV {
  position: absolute;
  width: 100%;
  background-color: lightblue;
  inset-block-start: 0;
}
</style>
</head>
<body>
<h1>Change inset-block-end property with JavaScript</h1>
<p>Click the "Try it" button to change the inset-block-end values of the DIV element:</p>
<button onclick="myFunction()">Try it</button>
<div id="parentDIV">
  <div id="myDIV">
    This is my DIV element.
  </div>
</div>
<script>
function myFunction() {
  document.getElementById("myDIV").style.insetBlockEnd = "100px";
}
</script>
</body>
</html>