{# A @page margin box. This template emits CSS, not markup -- the slot it
   fills lands inside the skeleton's `style` element -- so every interpolated
   value goes through `css_string` and never `escape_html`. HTML entities
   inside a stylesheet render literally, and neither filter's absence would
   stop a `</style>` in a firm name closing the block early. #}
{# A box that follows the section prints the named string the skeleton's
   section titles set (`string-set`, `string()`: print-engine features). Its
   label is a second string, seeded on a zero-height leaf after the cover and
   cleared by every section title, so it shows only on sheets before the
   first one -- a contents sheet -- and read with `last` so a sheet where the
   first section starts shows the section, not the label. #}
{% if follow %}
    .{{ running_string }}-start { string-set: {{ running_string }}-fallback "{{ running_label | css_string }}"; }
{% endif %}
    @page {
      @{{ running_box }} {
        content: {% if follow %}string({{ running_string }}-fallback, last) string({{ running_string }}, first){% else %}"{{ running_label | css_string }}"{% endif %}{% if show_page_number %} " · " counter(page) " / " counter(pages){% endif %};
        font-family: {{ font.label }};
        font-size: {{ size.type.micro }}px;
        color: {{ theme.text.light }};
      }
    }
    {# ...and not on the cover. A zero margin there does NOT suppress a margin
       box -- it renders anyway, clipped against the page edge, which is what
       the first PDF showed. Only `content: none` removes it. The region that
       put the box somewhere is what knows which one to blank. #}
    @page cover { @{{ running_box }} { content: none; } }
{% if skip_first %}
    {# The opening sheet carries no box (#400). `:first` outranks the bare rule
       and the count still runs, so sheet two reads 2. #}
    @page :first { @{{ running_box }} { content: none; } }
{% endif %}