chromium/third_party/blink/web_tests/fast/css/counters/counter-predefined-symbol.html

<!DOCTYPE html>
<style>
.columns {
  font-size: 26px;
  display: flex;
}
ol {
  padding-inline-start: 2em;
}

.disc {
  list-style-type: disc;
}
.disc-counter::marker {
  content: "[" counter(list-item, disc) "]";
}

.circle {
  list-style-type: circle;
}
.circle-counter::marker {
  content: "[" counter(list-item, circle) "]";
}

.square {
  list-style-type: square;
}
.square-counter::marker {
  content: "[" counter(list-item, square) "]";
}

.dc {
  list-style-type: disclosure-closed;
}
.dc-counter::marker {
  content: "[" counter(list-item, disclosure-closed) "]";
}
.dc-rtl {
  list-style-type: disclosure-closed;
}
.dc-rtl::marker {
  direction: rtl;
}
.dc-rtl-counter::marker {
  content: "[" counter(list-item, disclosure-closed) "]";
  direction: rtl;
}

.do {
  list-style-type: disclosure-open;
}
.do-counter::marker {
  content: "[" counter(list-item, disclosure-open) "]";
}

.counters::marker {
  content: counters(list-item, " => ", disclosure-closed);
}
</style>
<body>
<p>Symbols in a pairs for "disc", "circle", or "square" may have differences.
Triangles in a "Disclosure-*" pair should point to an identical direction.</p>

<div class="columns">
<ol style="flex: 1">
  <li class="disc">disc</li>
  <li class="disc-counter">disc</li>
  <li class="circle">circle</li>
  <li class="circle-counter">circle</li>
  <li class="square">square</li>
  <li class="square-counter">square</li>
  <li class="dc">disclosure-closed</li>
  <li class="dc-counter">disclosure-closed</li>
  <li class="dc-rtl">disclosure-closed in RTL</li>
  <li class="dc-rtl-counter">disclosure-closed in RTL</li>
  <li class="do">disclosure-open</li>
  <li class="do-counter">disclosure-open</li>
  <li>counters()
   <ol>
    <li class="counters">Sub-item</li>
   </ol>
  </li>
</ol>
<div>
<ol style="writing-mode: vertical-rl;">
  <li class="dc">disclosure-closed</li>
  <li class="dc-counter">disclosure-closed</li>
  <li class="do">disclosure-open</li>
  <li class="do-counter">disclosure-open</li>
</ol>
<ol style="writing-mode: vertical-lr;">
  <li class="dc">disclosure-closed</li>
  <li class="dc-counter">disclosure-closed</li>
  <li class="do">disclosure-open</li>
  <li class="do-counter">disclosure-open</li>
</ol>
</div>
<div>
<ol style="writing-mode: sideways-rl;">
  <li class="dc">disclosure-closed</li>
  <li class="dc-counter">disclosure-closed</li>
  <li class="do">disclosure-open</li>
  <li class="do-counter">disclosure-open</li>
</ol>
<ol style="writing-mode: sideways-lr;">
  <li class="dc">disclosure-closed</li>
  <li class="dc-counter">disclosure-closed</li>
  <li class="do">disclosure-open</li>
  <li class="do-counter">disclosure-open</li>
</ol>
</div>
</div>
</body>