stackoverflow.com/questions/1…
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
body {
border: 1px solid green;
}
.placeholder {
width: 50%;
padding-bottom: 50%;
background: rebeccapurple;
height: 0;
overflow: hidden;
}
</style>
</head>
<body>
<div class="placeholder">
text
</div>
</body>
</html>
