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                <!DOCTYPE html>
<html lang="en">
  <title>JavaScript and HTML</title>
  <meta charset="utf-8"/>
    function changeTitleCSSStyle() {
      var title = document.querySelector("#mainTitle"); = 'black'; = "yellow"; = "5px dashed red";
    <h1 id="mainTitle">My home page</h1> 

    <p>This is an example of interactivity between JavaScript and the HTML content of a document.</p>
    <button onclick="changeTitleCSSStyle();">Click me to change the CSS colors of the title of the page</button>


                h1 {
  border:12px solid violet;
  padding: 5px;
  border-radius: 15px;
  text-align: center;

p, h1 {
  font-family: cursive 

p, img, button {