{#- Full-screen screenshot viewer, opened by app.js from a thumbnail ([data-viewer]). -#}
<dialog class="viewer" id="viewer" aria-label="Screenshot">
  <div class="viewer-bar">
    <span class="viewer-count" aria-live="polite"></span>
    <button type="button" class="viewer-close" aria-label="Close (Esc)">Close</button>
  </div>
  <button type="button" class="viewer-nav viewer-prev" aria-label="Previous screenshot (←)">‹</button>
  <figure class="viewer-figure">
    <img class="viewer-img" alt="">
    <figcaption class="viewer-caption"></figcaption>
  </figure>
  <button type="button" class="viewer-nav viewer-next" aria-label="Next screenshot (→)">›</button>
</dialog>