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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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HTML 

              
                <p class="typewriter">You don't know about me without you have read a book by the name of The Adventures of Tom Sawyer; but that ain't no matter. That book was made by Mr. Mark Twain, and he told the truth, mainly. There was things which he stretched, but mainly he told the truth. That is nothing. I never seen anybody but lied one time or another, without it was Aunt Polly, or the widow, or maybe Mary. Aunt Polly - Tom's Aunt Polly, she is - and Mary, and the Widow Douglas is all told about in that book, which is mostly a true book, with some stretchers, as I said before.</p>
<p class="typewriter">- The Adventures of Huckleberry Finn, Mark Twain -</p>
!

CSS 

              
                body {
  background-color:#ffe;
  margin:4em;
  max-width:40em;
}

.typewriter {
  font-family:monospace;
  line-height:1.5;
}
!

JS 

              
                console.clear();

const typing = document.querySelectorAll('.typewriter');

function type(element) {

function randomOpacity() {
  return (Math.floor(Math.random() * 50) + 50)/100;
}

function randomEms() {
  if (Math.random() > .8) {
  return (Math.floor(Math.random() * 100) - 50)/800;
  }
  else {
    return 0;
  }
}

function wrap(char) {
  return '<span style="opacity:' + randomOpacity() + '; text-shadow:' + randomEms() + 'em ' + randomEms() + 'em currentColor;">' + char + '</span>';
}

const wrappedText = Array.from(element.textContent).map(wrap);

element.innerHTML = wrappedText.join('');
  
}

typing.forEach(type);
!
999px

Console