{% assign topics_by_letter = site.topic | group_by_exp: "topic", "topic.title | slice: 0, 1" | sort: "name" %}
{% for letter in topics_by_letter %} {% assign page_letter = page.title | slice: 0, 1 %} {% assign group_letter = letter.name | slice: 0, 1 %} {% assign first_in_group = letter.items.first %}
{% if page_letter == group_letter %} {{ group_letter }} {% else %} {{ group_letter }} {% endif %}
{% if page_letter == group_letter %}
{% for item in letter.items %}
{% if item.url == page.url %}
{{ item.title }}
{% else %} {{ item.title }} {% endif %}
{% endfor %}
{% endif %} {% endfor %}