Documentation

Any chance you can flesh out the documentation a bit? Trying to figure out how to use the focal point with a background image.

I’m calling the image field:

$image = get_field('background_image');

Then adding some inline CSS:
background: url(<?php echo $image['url']; ?>) no-repeat center center fixed;

But how do I get the top, left, right, bottom values? This doesn’t work:
top: <?php $image['top'];?>;

Thanks