Live Demo: change background color jquery

<!DOCTYPE html>
<html>
<head>
    <script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
</head>
<body>
    <h1>change background color by using jquery</h1>
   <button id="btn-bg">change bg color</button>
   <p>click on above button</p>
   <script>
     $(document).ready(function(){
         $("#btn-bg").click(function(){
             $("body").css("background-color","red");
         });
      });
   </script>
</body>
</html>