The head_css() helper function prints HTML link tags to the page for each stylesheet added
with queue_css_file. It is commonly used in a theme’s common/header.php file to print
the link tags inside the page head.
Get the CSS link tags that will be used on the page.
This should generally be used with echo to print the scripts in the page
Use after queue_css_file(), queue_css_url(), and/or queue_css_string() to add the links to the css files and/or the css declarations to the page head: