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<!DOCTYPE html>
<html>
<head>
</head>
<body>
<h1>JavaScript example </h1>
<p id ="demo">
  JavaScript can change the style of an HTML element.
</p>
<script>
  function myFunction() {
    x=document.getElementById("demo")
    x.style.color="#ff0000";
  }

</script>
<button type="button" onclick="myFunction()">Click Me!</button>
</body>
</html>