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                <div class="wrapper">
  <h1>Highlight Within Textarea v2</h1>
  <p>Highlight <input type="text" id="blue-word" value="possible"> in blue and <input type="text" id="pink-word" value="magic"> in pink.</p>
  <textarea spellcheck="false">The two words above are highlighted in this textarea. Such a thing isn't actually possible with HTML, but we can fake it with some CSS and JS magic. Go ahead, type some stuff in here or change the words above to see the real-time highlighting in action.</textarea>



                @import url(',700');

*, *::before, *::after {
  box-sizing: border-box;

html {
  min-height: 100%;

body {
  margin: 0;
  font: 1.5rem 'Asap', sans-serif;
  background-image: linear-gradient(120deg, #9890e3 0%, #b1f4cf 100%);

.wrapper {
  width: 650px;
  margin: 40px auto;
  text-align: center;

h1 {
  margin: 0 0 20px;
  font-size: 2.75rem;
  text-shadow: 2px 2px 0 rgba(255, 255, 255, 0.5);

p {
  margin: 0 0 40px;

input {
  appearance: none;
  display: inline-block;
  width: 100px;
  padding: 0;
  border: 0;
  border-bottom: 2px dashed #fff;
  border-radius: 0;
  text-align: center;
  font-size: inherit;
  font-family: inherit;
  font-weight: bold;
  background-color: transparent;

.hwt-container {
  background-color: rgba(255, 255, 255, 0.2);
  box-shadow: 0 0 50px rgba(0, 0, 0, 0.2);

.hwt-content {
  width: 650px;
  height: 225px;
  padding: 20px;
  border: 1px solid #fff;
  text-align: left;
  font-size: 1.5rem;
  line-height: 1.5;
  mark {
    border-radius: 2px;
    background-color: #fcc2d7;
    box-shadow: 0 0 0 1px #fff;
    &.blue {
      background-color: #a3daff;
    &.pink {
      background-color: #fcc2d7;



                // Uses highlight-within-textarea

function highlightBlue() {
  return $('#blue-word').val();

function highlightPink() {
  return $('#pink-word').val();

function updateHighlights() {

  highlight: [
      highlight: highlightBlue,
      className: 'blue'
      highlight: highlightPink,
      className: 'pink'

$('input').on('input', updateHighlights);