blowfish/layouts/shortcodes/gallery.html

{{ $time := now.UnixNano }}
{{ $id := delimit (slice "gallery" $time) "-" }}

<div id="{{ $id }}">
  {{ .Inner }}
</div>

<script>

  document.addEventListener("DOMContentLoaded", function () {
    var elem = document.querySelector('#{{ $id }}');
    var pckry = new Packery(elem, {
      percentPosition: true,
      gutter: 5,
      resize: true
    });
  });
</script>