{% macro page_back_link(page) %}
{% set top_section = get_section(path=page.ancestors | last) %}
<a class="previous" href="{{ top_section.permalink }}">‹ back</a>
{% endmacro page_back_link %}

{% macro section_back_link(section) %}
{% set top_section = get_section(path=section.ancestors | last) %}
<a class="previous" href="{{ top_section.permalink }}">‹ back</a>
{% endmacro section_back_link %}