Storing JQuery value to a free format hidden variable

Hi,

https://legacy.sawtoothsoftware.com/forum/34961/automatically-moving-slider-based-number-words-open-question

I have done with the above concept using the below code. However, I don't know how to store this text box value to a free format hidden variable.

Please help to store this text box value to a free format hidden variable.

 <script>

$(document).ready(function(){
// Bind "input" event to <textarea>
$('.text').on('input', wordCounter);

function wordCounter(event) {
  // Get the string value of .text
  const $count = $(this).val();
  /*
  Split that string value at every space into an array then return it's .length
  */
  const words = $count.split(' ').length;
  // Assign the word count value to <output> and <input>
  $('.display, .slider').val(words);
}
});

</script>


<style>
html {
  font: 300 2ch/1.2 'Segoe UI'
}

.box {
  display: flex;
  flex-flow: column nowrap;
  justify-content: center;
  width: max-content;
  padding-top: 12px;
  border: none;
}

input,
textarea {
  font: inherit;
}

.text {
  width: 57.5vw;
  height: 125px;
  padding: 4px 8px;
  resize: vertical;
}

.slider {
  -webkit-appearance: none;
  width: 58vw;
  height: 25px;
  background: #d3d3d3;
  outline: none;
  opacity: 0.7;
  transition: opacity .2s;
  pointer-events: none;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 25px;
  height: 25px;
  background: #04AA6D;
}

.slider::-moz-range-thumb {
  width: 25px;
  height: 25px;
  background: #04AA6D;
}

.display {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  width: 65vw;
  min-height: 25px;
  font-family: Consolas;
  border: none;
}
</style>
<script type="text/javascript">
alert($count);
</script>

<fieldset class="box">
  <textarea class='text' rows='5'></textarea>
  <td>&nbsp;</td>
  <input class='slider' type='range' min="0" max="20" value="0" readonly>
</fieldset>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>