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HTML

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Adding Classes

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About the <head>

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Insecure Resource

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CSS

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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 

              
                <main class="cards">
  <section class="card">
    <h2>Lorem Egestas Tristique Ligula</h2>
    <p>Donec id elit non mi porta gravida at eget metus. Maecenas faucibus mollis interdum. Nullam quis risus eget urna mollis ornare vel eu leo.</p>
  </section>
  <section class="card">
    <h2>Cras Fermentum Bibendum Dolor</h2>
    <p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Nullam quis risus eget urna mollis ornare vel eu leo.</p>
  </section>
  <section class="card">
    <h2>Pharetra Mattis Tristique Mollis Quam</h2>
    <p>Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit.</p>
  </section>
  <section class="card">
    <h2>Nullam Aenean</h2>
    <p>Vestibulum id ligula porta felis euismod semper. Nullam quis risus eget urna mollis ornare vel eu leo.</p>
  </section>
  <section class="card">
    <h2>Porta Venenatis Sollicitudin Pharetra</h2>
    <p>Nullam quis risus eget urna mollis ornare vel eu leo. Sed posuere consectetur est at lobortis.</p>
  </section>
  <section class="card">
    <h2>Fermentum Lorem Parturient Dapibus</h2>
    <p>Donec ullamcorper nulla non metus auctor fringilla. Aenean lacinia bibendum nulla sed consectetur.</p>
  </section>
</main>
!

CSS 

              
                :root {
  /* Sizes that the rest of our system will be based on */
  --ft-screen-width: 1440;
  --ft-body: 20;
  --ft-body-min: 0.75rem; /* Going this small for demo purposes */
  --ft-body-max: 2rem;
  --ft-body-vw: calc(var(--ft-body) / var(--ft-screen-width) * 100vw);
  
  /* Body, 20px on 1440px screens */
  --ft-size-body: clamp(var(--ft-body-min), var(--ft-body-vw), var(--ft-body-max));

  /* Heading, 26px on 1440px screens */
  --ft-heading: 26;
  --ft-size-heading: clamp(var(--ft-body-min) * (var(--ft-heading) / var(--ft-body)), var(--ft-body-vw) * (var(--ft-heading) / var(--ft-body)), var(--ft-body-max) * (var(--ft-heading) / var(--ft-body)));
}

body {
  --space-1rem: 1em;
  font-family: Georgia, serif;
  font-size: var(--ft-size-body);
  font-style: normal;
  font-weight: 400;
  line-height: 1.5;
  padding: 1em;
  text-transform: none;
  word-spacing: normal;
}

h2 {
  --space-1rem: 0.77em;
  font-family: sans-serif;
  font-size: var(--ft-size-heading);
  font-style: normal;
  font-weight: 400;
  line-height: 1.25;
  margin-bottom: calc(var(--space-1rem) - 0.25em);
  margin-top: 0;
  text-transform: uppercase;
  word-spacing: 0.15em;
}

p {
  margin-bottom: var(--space-1rem);
  margin-top: 0;
}

p:last-child {
  margin-bottom: 0;
}

.cards {
  column-gap: 1em;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  row-gap: 1em;
}

.card {
  border: 1px solid black;
  padding: 1em;
}
!

JS
!
999px

Console