bulma/docs/_includes/global/navbar-item.html

{% assign link = site.data.links.by_id[include.link_id] %}
{% assign cleanpath = link.path | remove_first: "/" %}

<a class="
  navbar-item
  bd-navbar-item
  bd-navbar-item-{{ link_id }}
  {{ include.class }}
  {% if page.route == cleanpath %}is-active{% endif %}
  {% if page.path contains '_posts' and link_id == 'blog' %}
    is-active
  {% endif %}
"
href="{{ site.url }}{{ link.path }}">
<span class="icon has-text-{{ link.color }}">
  <i class="{% if link.icon_brand %}fab{% elsif link.icon_regular %}far{% else %}fas{% endif %} fa-{{ link.icon }}"></i>
</span>

<span>{{ link.title }}</span>
</a>