/**
 * Recursive wp_parse_args WordPress function which handles multidimensional arrays
 * @url http://mekshq.com/recursive-wp-parse-args-wordpress-function/
 * @param  array &$a Args
 * @param  array $b  Defaults
 */
function zn_wp_parse_args(&$a, $b)
{
    $a = (array) $a;
    $b = (array) $b;
    $result = $b;
    foreach ($a as $k => &$v) {
        if (is_array($v) && isset($result[$k])) {
            $result[$k] = zn_wp_parse_args($v, $result[$k]);
        } else {
            $result[$k] = $v;
        }
    }
    return $result;
}
<?php

/**
 * Display Header's HTML markup
 */
$inner = array('left' => array('alignment_x' => 'fxb-start-x', 'alignment_y' => 'fxb-center-y', 'stretch' => 'fxb-basis-auto'), 'center' => array('alignment_x' => 'fxb-center-x', 'alignment_y' => 'fxb-center-y', 'stretch' => 'fxb-basis-auto'), 'right' => array('alignment_x' => 'fxb-end-x', 'alignment_y' => 'fxb-center-y', 'stretch' => 'fxb-basis-auto'));
$flexbox_scheme_defaults = array('top' => $inner, 'main' => $inner, 'bottom' => $inner);
// Extend Flexbox scheme defaults
$flexbox_scheme = zn_wp_parse_args($flexbox_scheme, $flexbox_scheme_defaults);
// START MARKUP
// place a hook before markup
do_action('zn_before_siteheader_inside');
// Area checks - TOP
$check_top = has_action('zn_head__top_left') || has_action('zn_head_left_area') || has_action('zn_head_left_area_s7') || has_action('zn_head_left_area_s9') || has_action('zn_head__top_right') || has_action('zn_head_right_area') || has_action('zn_head_right_area_s7') || has_action('zn_head_right_area_s9');
// Area checks - BOTTOM
$check_bottom = has_action('zn_head__bottom_left') || has_action('zn_head__bottom_center') || has_action('zn_head__bottom_right') || has_action('zn_head_cart_area_s8') || has_action('zn_head__before__bottom') || has_action('zn_head__after__bottom');
// Add Classes to Main if no Top/Bottom
$main_class = '';
$main_class .= !$check_top ? ' header-no-top' : '';
$main_class .= !$check_bottom ? ' header-no-bottom' : '';
?>
<div class="site-header-wrapper <?php 
echo $sticky_class ? $sticky_class : '';
?>
">

    <div class="kl-top-header site-header-main-wrapper clearfix">

        <div class="container siteheader-container <?php 
echo $siteheader_container_class ? $siteheader_container_class : '';
?>