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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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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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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-.

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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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HTML 

              
                <div class="worklet-canvas"></div>
<div class="prompt">
  <p>
    Psst... resize the browser and watch the pattern re-arrange itself! ✨
  </p>
  <div class="prompt__buttons">
    <a class="prompt__button prompt__button--fullscreen" href="https://cdpn.io/georgedoescode/debug/db3de4da463af459f040d517827ca22b" target="_blank">Full Screen</a>
    <button class="prompt__button prompt__button--regenerate">Regenerate</button>
  </div>

</div>
!

CSS 

              
                * {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100vw;
  height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Poppins", sans-serif;
  line-height: 1.5;
  background: #1d1934;
  color: #1d1934;
  padding: 1.5rem;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.worklet-canvas {
  --fluid-pattern-seed: 123456;
  --fluid-pattern-bg-color: #1d1934;
  --fluid-pattern-color-1: #ffd53d;
  --fluid-pattern-color-2: #f0f1ff;
  --fluid-pattern-color-3: #f25c54;
  --fluid-pattern-color-4: #48cb8a;

  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;

  background-image: paint(fluidPattern);
}

.prompt {
  position: relative;
  padding: 1.5rem;
  background: hsla(0, 100%, 100%, 0.75);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  backdrop-filter: blur(16px) saturate(180%);
  box-shadow: 0px 4px 16px 0px hsla(0, 0%, 0%, 0.125);
  border-radius: 1rem;
  z-index: 1;
  border: 1px solid hsla(0, 0%, 100%, 0.9);
  font-weight: 700;
  letter-spacing: -0.025em;
  max-width: 26rem;
  text-align: center;
}

.prompt p {
  font-size: 1.125rem;
  margin-bottom: 1.5rem;
}

.prompt__buttons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-gap: 1rem;
}

.prompt__button {
  width: 100%;
  display: block;
  height: 2.75rem;
  line-height: 2.75rem;
  background: #1d1934;
  color: #fff;
  border: 0;
  font-weight: 600;
  border-radius: 0.5rem;
  font-family: inherit;
  cursor: pointer;
  font-size: 0.875rem;
  text-decoration: none;
}

.prompt__button--fullscreen {
  background: #fff;
  color: #1d1934;
}

@media only screen and (max-width: 480px) {
  .prompt__buttons {
    grid-template-columns: 1fr;
  }
}
!

JS 

              
                (async function () {
  // Uh oh! No Paint API support...
  if (CSS["paintWorklet"] === undefined) {
    // Let the user know they can't experiment with the pattern
    document.querySelector(
      ".prompt p"
    ).innerHTML = `Ah... the CSS Paint API is not supported in this browser — try Chrome or Edge!`;

    // Disable the regeneration button
    document.querySelector(".prompt__button--regenerate").style.opacity = "0.5";
    document.querySelector(".prompt__button--regenerate").style.pointerEvents =
      "none";
  } else {
    // Source: https://github.com/georgedoescode/fluid-pattern-worklet/blob/main/worklet.js
    CSS.paintWorklet.addModule(
      "https://unpkg.com/@georgedoescode/fluid-pattern-worklet"
    );
    // Update the pattern seed on click
    document
      .querySelector(".prompt__button--regenerate")
      .addEventListener("click", () => {
        document
          .querySelector(".worklet-canvas")
          .style.setProperty("--fluid-pattern-seed", Math.random() * 10000);
      });
  }

  if (!inIframe()) {
    document.querySelector(".prompt__button--fullscreen").style.display =
      "none";
    document.querySelector(".prompt__buttons").style.gridTemplateColumns =
      "1fr";
  }
})();

function inIframe() {
  try {
    return window.self !== window.top;
  } catch (e) {
    return true;
  }
}
!
999px

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