Prints colours of event categories to header on front-end

event-categorgy-color.php

<?php
/**
 * Prints colours of event categories to header on front-end
 * @See http://wp-event-organiser.com/blog/tutorial/using-event-colours-in-your-theme/
 * @See http://wp-event-organiser.com/blog/tutorial/adding-event-colour-to-your-menu/
 *
*/
add_action( 'wp_print_styles', 'my_print_event_cat_colours' );
function my_print_event_cat_colours(){

    $cats = get_terms( 'event-category' );
    if( $cats ){

        echo '<style>';
        foreach( $cats as $cat ){
                 printf( 
                      ".event-category-%s{ background: %s;}\n", 
                      sanitize_html_class( $cat->slug ), 
                      eo_get_category_color( $cat ) 
                 ); 
        }
        echo '</style>';
    }
}