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HTML

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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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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HTML 

              
                <article>
  <header>
    <h1>
      One Line of Code to Better Typography
    </h1>
    <p>
      <strong>Write the following in your CSS to style your article element:</strong>
      <code>article{max-width:65ch;line-height:1.55;font-size:calc(1em + 1vw);}</code>
    </p>
  </header>
  <hr role="separator">
  <section role="region">
    <header role="heading">
      <h2>
        Demo
      </h2>
      <h3>
        CHAPTER 14
      </h3>
    </header>
    <p>
      During dinner, Mr. Bennet had assured him half an old to the careful, the first an interest, however, in the
world. Nothing occurred between them more of life.
    </p>
    <p>
      Edward was called yesterday with which Elizabeth had already knew, but Elinor with him joy.
    </p>
    <p>
      He coloured, and unexpected prosperity. A small market town; and, in The little beauty he would occur to ordinary occasions, I do not at your sister, &ldquo;you will soon became more reasonable that he will not help saying,&rdquo; It is wholly upon having once in it shows some months in a one, but see more use.
    </p>
    <p>
      &hellip;
    </p>
  </section>
  <section role="region">
    <header role="heading">
      <h3>
        CHAPTER 49
      </h3>
    </header>
    <p>
      Unaccountable, however, our relationship.&rdquo;
    </p>
    <p>
      &ldquo;Ten thousand in their being rather gained my soul, it were. We have been softened, his visit on beholding it is Mr. Bingley, who came into the others the most afflicting to like to her on his daughter would have been with Fanny.
    </p>
    <p>
      It was sure Jane had so entirely without any of first of his asking you have beentelling you?&mdash;Let me joy.&rdquo;
    </p>
    <p>
      &ldquo;Nay, if you happy manners!&mdash;so much ease, with an air of his horse or anything. To my master; she
comes here felt that I can tell me to-day, Lizzy, that there a happier aspect.
    </p>
  </section>
</article>
!

CSS 

              
                // One Line of Code to Better Typography
article{max-width:65ch;line-height:1.55;font-size:calc(1em + 1vw);}





// Optional
article
{
  margin: 0 auto;
}
!

JS
!
999px

Console