Using the Bootstrap framework will open endless possibilities on how to display your divs and containers, plus, it's responsive and works great with almost every device out there !
Check Here to learn more about BS
what you want to achieve can be easily done with the following :
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<div class="row">
<div class="col-sm-3">
<center>Ad Here ! </center>
</div>
<div class="col-sm-6">
<center>Main Content </center>
</div>
<div class="col-sm-3">
<center>Ad Here ! </center>
</div>
</div>
</div>
</body>
</html>