<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
iframe {
height: 250px;
width: 300px;
background-color: #c6c7af;
}
body {
text-align: center;
}
</style>
</head>
<body>
<h1>Example</h1>
<iframe src="https://www.w3docs.com/" frameBorder="0"></iframe>
</body>
</html>