<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>HTML</title>
<style>
.container {
height: 100vh;
background-color: #cccccc;
}
</style>
</head>
<body>
<div class="container">
<h2> Full height container </h2>
</div>
</body>
</html>