CSS Pseudo Element Counters: can you increment an alphabet letter "a", "b", "c", etc instead of a number?

ul {
  counter-reset: listStyle;
}
ul li {
  margin-left: 1em;
  counter-increment: listStyle;
}
ul li::before {
  margin-right: 1em;
  content: counter(listStyle, lower-alpha);
}

<ul>
  <li>one</li>
  <li>two</li>
  <li>three</li>
</ul>

let select = document.querySelector('select'),
  output = document.querySelector('#currentCounter'),
  changeEvent = new Event('change');

select.addEventListener('change', function() {
  document.body.style.setProperty('--listStyleType', this.value);
  output.textContent = this.value;
});

select.dispatchEvent(changeEvent);

body {
  --listStyleType: decimal;
}

ul {
  counter-reset: listStyle;
  columns: 2;
  margin-top: 0.5em;
  list-style-type: none;
}

ul li {
  counter-increment: listStyle;
}

ul li::before {
  content: counter(listStyle, var(--listStyleType));
  display: inline-block;
  margin-right: 0.5em;
  width: 1.5em;
  height: 1.5em;
  line-height: 2em;
  text-align: center;
}

code {
  display: block;
  white-space: pre-wrap;
  width: 80%;
  box-sizing: border-box;
  margin: 1em auto;
  padding: 0.5em;
  box-shadow: 0 0 0 3px limegreen;
}

code::after {
  content: '\A';
}

#currentCounter {
  color: #f90;
}

<label for="counterChoice">Please select a CSS counter:</label>
<select id="counterChoice">
  <option value="arabic-indic">arabic-indic</option>
  <option value="armenian">armenian</option>
  <option value="bengali">bengali</option>
  <option value="cambodian">cambodian</option>
  <option value="circle">circle</option>
  <option value="cjk-decimal">cjk-decimal</option>
  <option value="cjk-earthly-branch">cjk-earthly-branch</option>
  <option value="cjk-heavenly-stem">cjk-heavenly-stem</option>
  <option value="decimal">decimal</option>
  <option value="decimal-leading-zero">decimal-leading-zero</option>
  <option value="devanagari">devanagari</option>
  <option value="disc">disc</option>
  <option value="disclosure-closed">disclosure-closed</option>
  <option value="disclosure-open">disclosure-open</option>
  <option value="ethiopic-numeric">ethiopic-numeric</option>
  <option value="georgian">georgian</option>
  <option value="gujarati">gujarati</option>
  <option value="gurmukhi">gurmukhi</option>
  <option value="hebrew">hebrew</option>
  <option value="hiragana">hiragana</option>
  <option value="hiragana-iroha">hiragana-iroha</option>
  <option value="japanese-formal">japanese-formal</option>
  <option value="japanese-informal">japanese-informal</option>
  <option value="kannada">kannada</option>
  <option value="katakana">katakana</option>
  <option value="katakana-iroha">katakana-iroha</option>
  <option value="khmer">khmer</option>
  <option value="korean-hangul-formal">korean-hangul-formal</option>
  <option value="korean-hanja-formal">korean-hanja-formal</option>
  <option value="korean-hanja-informal">korean-hanja-informal</option>
  <option value="lao">lao</option>
  <option value="lower-alpha">lower-alpha</option>
  <option value="lower-alpha">lower-alpha</option>
  <option value="lower-armenian">lower-armenian</option>
  <option value="lower-greek">lower-greek</option>
  <option value="lower-latin">lower-latin</option>
  <option value="lower-roman">lower-roman</option>
  <option value="malayalam">malayalam</option>
  <option value="mongolian">mongolian</option>
  <option value="myanmar">myanmar</option>
  <option value="oriya">oriya</option>
  <option value="persian">persian</option>
  <option value="simp-chinese-formal">simp-chinese-formal</option>
  <option value="simp-chinese-informal">simp-chinese-informal</option>
  <option value="square">square</option>
  <option value="tamil">tamil</option>
  <option value="telugu">telugu</option>
  <option value="thai">thai</option>
  <option value="tibetan">tibetan</option>
  <option value="trad-chinese-formal">trad-chinese-formal</option>
  <option value="trad-chinese-informal">trad-chinese-informal</option>
  <option value="upper-alpha">upper-alpha</option>
  <option value="upper-armenian">upper-armenian</option>
  <option value="upper-latin">upper-latin</option>
  <option value="upper-roman">upper-roman</option>
</select>
<ul>
  <li>one</li>
  <li>two</li>
  <li>three</li>
  <li>four</li>
  <li>five</li>
  <li>six</li>
  <li>seven</li>
  <li>eight</li>
  <li>nine</li>
  <li>ten</li>
</ul>

<code>
  li::before {
    content: counter(&lt;counterName&gt;, <span id="currentCounter"></span>)
  }
</code>