responsive

<!DOCTYPE html>
<html>
<head>
	<title></title>
	<meta name="viewport" content="width=device-width, initial-scale=1.0" charset="utf-8">
	<style type="text/css">
		@media (min-width: 800px) {
			h1::before {
				content: "Welcome to My Web"
			}
		}

		@media (max-width: 799px) {
			h1::before {
				content: "Welcome!"
			}
		}
	</style>
</head>
<body>
	<h1></h1>
</body>
</html>