stname.match(/^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/)
        );
        if (!isLocalhost) {
            window.addEventListener("load", () => {
                navigator.serviceWorker.register("{{ '/sw.js'|resolveFile }}");
            });
        }
    }
</script>
{% endblock %}
{% block book_inner %} {{ super() }}
<footer class="book_footer">
    <p>Copyright (c) 2016-present <a href="https://github.com/asciidwango/js-primer">jsprimer project</a></p>
</footer>
{% endblock %}
