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Babel includes JSX processing.

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Code Indentation

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                <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Blanditiis dicta, placeat tenetur fuga, eaque voluptas cupiditate tempora aperiam expedita, cum ab molestias consequatur tempore veniam temporibus omnis excepturi debitis ea!</p>

<details class="ContentWarning">
    <strong>⚠️ Content warning:</strong> 
      alt="Juicy burger and fries on a wooden board"

<p>Lorem ipsum, dolor sit amet consectetur adipisicing elit. Assumenda quia quae corrupti expedita, harum deserunt quasi tempore dicta illo, repudiandae illum, aliquid nobis esse nemo unde voluptatum ratione et aperiam.</p>


                body {
  font: 125% / 1.4 sans-serif;
  max-width: 600px;
  margin: 1em auto;
  padding: 1em;

img {
  max-width: 100%;
  display: block;
  height: auto;

.ContentWarning {
  border: 1px solid rgb(0 0 0 / 0.3);
  border-radius: 0.2em;
  padding: 1em;

.ContentWarning > summary {
  position: relative;
  list-style: none;
  cursor: pointer;
  padding: 1em;
  margin: -1em;
  --stripe-color: rgb(0 0 0 / 0.1);
  background-image: repeating-linear-gradient(
    transparent 0.5em,
    var(--stripe-color) 0.5em,
    var(--stripe-color) 1em

.ContentWarning > summary::after {
  content: '↕ expand';
  text-transform: uppercase;
  letter-spacing: 1px;
  opacity: 0.8;
  font-size: 70%;
  position: absolute;
  right: 1em;
  top: 50%;
  transform: translatey(-50%);

.ContentWarning[open] > summary {
  margin-bottom: 1em;

.ContentWarning > summary:hover,
.ContentWarning > summary:focus {
  --stripe-color: rgb(150 0 0 / 0.1);