body {
	background-image: url('https://www.bouwmeestersvanmanen.nl/images/backdrop.jpg');
	background-repeat: no-repeat;
	background-attachment: fixed;
	background-position: center; 
	background-size: cover;
}
div.containermain {
  background-color: rgba(255, 255, 255, 0.9);
  border-radius: 16px;
}