MM.html

<!DOCTYPE html>

<html>
<head>
	<meta charset="UTF-8">
	<title></title>
	<style type="text/css">
		html,body{
			height: 100%;
    		margin: 0;
       				}
		
		.back{
			background-image: url("photo_2017-08-02_17-30-32.jpg");
			/* Full height */
			height:177.5vw;

    		/* Center and scale the image nicely */
    		background-position: left top;
    		background-repeat: no-repeat;
    		background-size: cover ;
					}
		.btn{
			z-index:10;
			width:100%;
			height:40vh;
			position: absolute;
			background-color:white;
			opacity:0.5;
			top:293%; 
		}
	</style>
</head>
<body>
<div class="back">
	<img src="">
</div>
<div class="btn"></div>
</body>
</html>