A site-wide banner in WooCommerce / WordPress

site-wide-banner-wordpress-woocommerce.php

<?php // For implementation instructions see: https://aceplugins.com/how-to-add-a-code-snippet/

/**
 * Basic site-wide banner.
 */
function ace_custom_site_banner() {
    ?><div class="site-banner">
        <span>
            <strong style="">Sale!</strong> Get up to 50% off, sale ending this friday.
        </span>
    </div><?php
}
add_action( 'wp_footer', 'ace_custom_site_banner' );