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HTML

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About the <head>

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Insecure Resource

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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.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

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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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

All packages are different, so refer to their docs for how they work.

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HTML 

              
                <section class="hero uk-background-cover uk-background-norepeat" style="--bg-image-mobile: url(https://assets.codepen.io/162656/bg-hero-mobile.jpg);--bg-image-tablet: url(https://assets.codepen.io/162656/bg-hero-tablet.jpg);--bg-image-desktop: url(https://assets.codepen.io/162656/bg-hero-desk.jpg)">
  <div class="uk-container uk-container-small">
    <div class="uk-background-muted uk-padding">
      <h1>Heading</h1>
      <p class="uk-h3">Vivamus finibus lectus arcu. Nulla at sapien sed nisl tincidunt dictum sed vitae sapien. Aenean egestas lectus sed enim consectetur finibus. In in nunc in ligula cursus luctus. Nulla facilisi.</p>
    </div>
  </div>
</section>
<section class="uk-padding-large">
  <div class="uk-container uk-container-small">
    <h2 class="uk-h1">Another Heading</h2>
    <p class="uk-h4"> Quisque semper ante turpis, sed mollis libero aliquet eu. Mauris eget consectetur neque. Nam id feugiat tellus. Sed tempus lorem porta nulla finibus, id dapibus ligula aliquet. Morbi in gravida nulla. Fusce pharetra dui ligula, eget condimentum urna venenatis vel.</p>
    <p class="uk-h4">Etiam varius sagittis arcu vitae vulputate. Praesent quis nibh sed dolor imperdiet porta. Pellentesque sed est in ante volutpat aliquam quis nec ligula. Donec lorem elit, lobortis at mi a, pellentesque mattis augue.</p>
    <p class="uk-h4">Aenean vulputate purus sit amet odio mattis tincidunt. Praesent ornare est nec lacus dapibus cursus. Vivamus finibus lectus arcu. Nulla at sapien sed nisl tincidunt dictum sed vitae sapien. Aenean egestas lectus sed enim consectetur finibus. In in nunc in ligula cursus luctus. Nulla facilisi.</p>
  </div>
</section>
<footer class="page-footer">
  <span>made by </span>
  <a href="https://georgemartsoukos.com/" target="_blank">
    <img width="24" height="24" src="https://assets.codepen.io/162656/george-martsoukos-small-logo.svg" alt="George Martsoukos logo">
  </a>
</footer>
!

CSS 

              
                body {
  background: #efefef;
}

.uk-background-muted {
  background: rgba(248, 248, 248, 0.75);
  backdrop-filter: blur(10px);
}

.hero {
  padding: 20vh 0;
  background-image: var(--bg-image-mobile);
}

@media (min-width: 960px) {
  .hero {
    background-image: var(--bg-image-tablet);
  }
}

@media (min-width: 1200px) {
  .hero {
    background-image: var(--bg-image-desktop);
  }
}

/* FOOTER STYLES
–––––––––––––––––––––––––––––––––––––––––––––––––– */
.page-footer {
  position: fixed;
  right: 0;
  bottom: 50px;
  display: flex;
  align-items: center;
  padding: 5px;
  background: #fff;
}

.page-footer a {
  display: flex;
  margin-left: 4px;
}
!

JS
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999px

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