cyclone/_includes/base.html

{% assign base = '' %}
{% assign depth = page.url | split: '/' | size | minus: 1 %}
{% if    depth == 1 %}{% assign base = '.' %}
{% elsif depth == 2 %}{% assign base = '..' %}
{% elsif depth == 3 %}{% assign base = '../..' %}
{% elsif depth == 4 %}{% assign base = '../../..' %}{% endif %}