I use Custom CSS Plugin.
I had inserted your code but it doesn’t work.
See my footer code:
?>
</div><!-- #main .site-main -->
<footer id="colophon" class="site-footer" role="contentinfo">
<div class="site-info">
<?php do_action( 'spun_credits' ); ?>
<a href="https://www.ads-software.com/" title="<?php esc_attr_e( 'A Semantic Personal Publishing Platform', 'spun' ); ?>" rel="generator"><?php printf( __( 'Powered by %s', 'spun' ), 'WordPress' ); ?></a>
<span class="sep"> | </span>
<?php printf('Thème %1$s ', 'spun' ); ?>
<span class="sep"> | </span>
<?php printf('Copyright 2013 - Tous droits réservés'); ?>
</div><!-- .site-info -->
</footer><!-- #colophon .site-footer -->
</div><!-- #page .hfeed .site -->
<?php wp_footer(); ?>
</body>
</html>
I think the problem comes from the footer.php