<!DOCTYPE html>
<html>
<head>
<style>
body, html {
    margin: 0;
}

div {
    position: absolute;
    top: 0;
    left: 0;
    width: 400px;
    height: 400px;
    background-size: contain;
    background-image: url(../../resources/green-400x400.png);
}
</style>
</head>
<body>
<div></div>
</body>
</html>