{% if page.layout == “post” or page.layout == “blog” or page.layout == “page” %} <!–

<div class="byline">
        <span class="author">{{ site.author.short_name }}</span>
        <span class="date">{{ page.date | date: "%a, %-d %b, %Y" }}</span>
</div>

–> {% else %}

<!-- this page type has no byline -->

{% endif %}