{%- assign default_paths = site.pages | map: "path" -%}
{%- assign page_paths = site.header_pages | default: default_paths -%}
{%- assign titles_size = site.pages | map: 'title' | join: '' | size -%}
<header class="d-flex flex-wrap justify-content-center py-3 mb-4 border-bottom">
    <a href="{{ "/" | relative_url }}" class="d-flex align-items-center mb-3 mb-md-0 me-md-auto text-dark text-decoration-none">
        {%- if site.jekyll-twitter-bootstrap.logo.header -%}
            {{ site.jekyll-twitter-bootstrap.logo.header }}
        {%- else -%}
            <svg class="bi me-2" width="40" height="32"><use xlink:href="/assets/svg/bootstrap.svg#bootstrap"/></svg>
        {%- endif -%}
        <span class="fs-4">{{ site.title | escape }}</span>
    </a>
    {%- if titles_size > 0 -%}
        <ul class="nav nav-pills">
            {%- for path in page_paths -%}
                {%- assign this_page = site.pages | where: "path", path | first -%}
                {%- if this_page.title -%}
                    {%- if this_page.url == page.url -%}
                        {% assign class = 'active' %}
                        {% assign aria = 'aria-current="page"' %}
                    {%- endif -%}
                    <li class="nav-item"><a href="{{ this_page.url | relative_url }}" class="nav-link {{ class }}" {{ aria }}>{{ this_page.title | escape }}</a></li>
                    {% assign class = nil %}
                    {% assign aria = nil %}
                {%- endif -%}
            {%- endfor -%}
        </ul>
    {%- endif -%}
    {% include header_custom.html %}
</header>