to HTML & CSS
The BLUE BOX below has been created by the HTML & CSS code.   Read below to find out how...

<html> <!-- HTML start -->

<head>

<style type="text/css"><!-- CSS start -->

#box1 {
width: 215px;
height: 260px;
background-color: blue
}
  <!-- CSS end -->
</style>

</head>

<body>

<div id="box1">   </div>

</body>

</html><!-- HTML end -->