Add custom inline styles to the Cookbook print/print preview.

cookbook-print.php

<?php

add_action( 'cookbook_recipe_print_head', 'prefix_cookbook_inline_print_css', 99 );
/**
 * Inline custom print styles in the Cookbook print head.
 *
 * @since  1.0.0
 * @access public
 * @return void
 */
function prefix_cookbook_inline_print_css() {
	?>
	<style>
	.cookbook-recipe-print-body {
		font-size: 14px;
	}

	.cookbook-nutrition {
		page-break-before: avoid;
	}
	</style>
	<?php
}