Check for Astra Advanced Headers and add header ID class to Wordpress body classes for per-header styling

gistfile1.txt

/** 
 * Check for Astra Advanced Headers and add header ID class to body classes for per-header styling
 * @author Tristan Mason <tristanmason.com>
 */
function tmac_add_advanced_header_class( $classes ) {
    // only run if Advanced Headers exists and is enabled on this page
    if ( (int)method_exists('Astra_Ext_Advanced_Headers_Data', 'get_current_page_header_ids') && in_array('ast-advanced-headers',$classes) ) {
        $tmac_header_ids = Astra_Ext_Advanced_Headers_Data::get_current_page_header_ids();
        $classes[] = 'tmac-header-id-' . $tmac_header_ids;
    }

    return $classes;
}
add_action( 'body_class', 'tmac_add_advanced_header_class', 15 );