[Theme: Carrington] where and how to edit header margins

Hello,
I have an annoying gap above my header image and have not been able to identify the template I need to edit, or which changes I should make. The site is: https://www.fridaycircle.com and I’d like the header image to be flush with the top of the page. The closest I came to finding how to edit the margins and wrapping was in functions.php

<style type="text/css">
#header .wrapper {
	background-image: url(<?php echo $img[0]; ?>);
	background-repeat: no-repeat;
	height: <?php echo $img[2]; ?>px;
}
</style>
<?php
		}
		else {
?>
<style type="text/css">
#header .wrapper {
	background-image: url();
}
</style>

but I’m still unsure if this is the code I need to change (header-default.php seems to be something different) and how to make the changes. Any/all advice most gratefully received! Thanks.