acf/input/admin_footer

Description
Used to output additional 
<body> HTML to pages where ACF fields appear.
This action is similar to the WordPress admin_footer, except that it is only fired on pages where ACF fields appear – such as when editing posts, users, taxonomy terms, options pages and front-end forms.
Changelog
Added in version 5.0.0
Example
This example demonstrates how to output additional inline style and script tags to customize fields.
functions.php
<?php
add_action('acf/input/admin_footer', 'my_acf_admin_footer');
function my_acf_admin_footer() {
    ?>
    <style type="text/css">
        /* CSS here. */
    </style>
    <script type="text/javascript">
    (function( $ ){
        // Javascript here.
    })(jQuery);
    </script>
    <?php
}