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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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Adding Classes

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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

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <section>
  <h1>CSS Color-Mix() - Art Class Demo</h1>

  <p>Using the CSS color-mix() function, we're able to mix primary and secondary colors to form a linear color 'wheel'. This feature is currently (15.4.2022) only available behind flags in Firefox and <a href="https://developer.apple.com/safari/technology-preview/">Safari Technology Preview</a>.</p>

  <section class="wheel">
    <div class="primary one"></div>
    <div class="tertiary one"></div>
    <div class="secondary one"></div>
    <div class="tertiary two"></div>
    <div class="primary two"></div>
    <div class="tertiary three"></div>
    <div class="secondary two"></div>
    <div class="tertiary four"></div>
    <div class="primary three"></div>
    <div class="tertiary five"></div>
    <div class="secondary three"></div>
    <div class="tertiary six"></div>
    <div class="primary one"></div>
  </section>

</section>

<div class="not-supported">The color-mix() feature is not supported in your browser.</div>
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CSS 

              
                .wheel {
  --primary-1: #ff0;
  --primary-2: #f00;
  --primary-3: #00f;
  --secondary-1: color-mix(in hwb, var(--primary-1) 50%, var(--primary-2));
  --secondary-2: color-mix(in hwb, var(--primary-2) 50%, var(--primary-3));
  --secondary-3: color-mix(in hwb, var(--primary-3) 50%, var(--primary-1));
  --tertiary-1: color-mix(in hwb, var(--primary-1) 50%, var(--secondary-1));
  --tertiary-2: color-mix(in hwb, var(--secondary-1) 50%, var(--primary-2));
  --tertiary-3: color-mix(in hwb, var(--primary-2) 50%, var(--secondary-2));
  --tertiary-4: color-mix(in hwb, var(--secondary-2) 50%, var(--primary-3));
  --tertiary-5: color-mix(in hwb, var(--primary-3) 50%, var(--secondary-3));
  --tertiary-6: color-mix(in hwb, var(--secondary-3) 50%, var(--primary-1));

  align-items: center;
  display: flex;
  justify-content: space-between;
  pading-block-end: 1rem;

  div {
    border-radius: 4px;
    transition: all 0.1s ease;

    &:hover {
      transform: scaleY(1.1);
      transform-origin: center;
    }
  }

  .primary {
    block-size: 150px;
    inline-size: 25px;

    &.one {
      background: var(--primary-1);
    }
    &.two {
      background: var(--primary-2);
    }
    &.three {
      background: var(--primary-3);
    }
  }

  .secondary {
    block-size: 125px;
    inline-size: 20px;

    &.one {
      background: var(--secondary-1);
    }
    &.two {
      background: var(--secondary-2);
    }
    &.three {
      background: var(--secondary-3);
    }
  }
  .tertiary {
    block-size: 100px;
    inline-size: 15px;

    &.one {
      background: var(--tertiary-1);
    }
    &.two {
      background: var(--tertiary-2);
    }
    &.three {
      background: var(--tertiary-3);
    }
    &.four {
      background: var(--tertiary-4);
    }
    &.five {
      background: var(--tertiary-5);
    }
    &.six {
      background: var(--tertiary-6);
    }
  }
}

/* GLOBAL */
:root {
  --body-bg: #f0efeb;
  --color-text: #000;
  --color-link: #011627;

  --color-primary: #fcca46;
  --color-secondary: #e71d36;
  --color-accent: #00afb9;

  --scrollbar-bg: #222;
}

body::-webkit-scrollbar {
  width: 10px;
}
body {
  scrollbar-width: thin;
  scrollbar-color: var(--color-primary) var(--scrollbar-bg);
}
body::-webkit-scrollbar-track {
  background: var(--scrollbar-bg);
}
body::-webkit-scrollbar-thumb {
  background-color: var(--color-primary);
  border-radius: 6px;
  border: 3px solid var(--scrollbar-bg);
}

html,
body {
  color: var(--color-text);
  font-family: "Barlow", sans-serif;
  font-size: 100%;
  letter-spacing: 0.25px;
  line-height: 1.75;
  margin: 0;
  padding: 0;
}

body {
  background: var(--body-bg);
  background: linear-gradient(
    50deg,
    var(--color-secondary) 0%,
    var(--color-secondary) 5%,
    var(--color-primary) 5%,
    var(--color-primary) 12%,
    var(--body-bg) 12%,
    var(--body-bg) 13%,
    var(--color-accent) 13%,
    var(--color-accent) 14%,
    var(--body-bg) 14%
  );
  block-size: 100%;
  display: grid;
  min-block-size: 100vh;
  place-items: center;
}

a {
  color: var(--color-link);
  text-decoration: underline 1px dashed;
  text-underline-offset: min(5px, 1em);

  &:hover {
    color: color-mix(in srgb, var(--color-link) 90%, var(--color-secondary));
  }

  &:focus {
    outline: 1px solid currentColor;
    outline-offset: 3px;
  }
}

h1,
h2 {
  font-family: "Hubballi", cursive;
  line-height: 1.25;
}

section {
  inline-size: min(750px, 60vw);
}

.not-supported {
  background: #600;
  border-radius: 8px;
  color: #fff;
  font-size: 0.9rem;
  padding: 0.5rem 1rem;
  position: fixed;
  inset-block-end: 1rem;
  inset-inline-start: 1rem;

  @supports (background: color-mix(in srgb, #34c9eb 10%, white)) {
    display: none;
  }
}
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JS
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