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HTML

              
                <section>
  <h1>CSS Color-Contrast() - Text and ::selection Demo</h1>

  <article>
    <h2>The Shining</h2>
    <p>A family heads to an isolated hotel for the winter where a sinister presence influences the father into violence, while his psychic son sees horrific forebodings from both past and future.</p>
  </article>

  <article>
    <h2>Incident in a Ghostland</h2>
    <p>A mother of two who inherits a house is confronted with murderous intruders on the first night in their new home and fights for her daughters' lives. Sixteen years later when the daughters reunite at the house, things get really strange.</p>
  </article>

  <p>🚀 Bonus: Highlight the text on the page to see the ::selection background use color-contrast().</p>
</section>

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

CSS

              
                article {
  --article-bg: #e9d8a6;
  --article-color: color-contrast(var(--article-bg) vs #fff, #000);

  background: var(--article-bg);
  color: var(--article-color);
  padding: 0.5rem 1rem;

  &:last-of-type {
    --article-bg: #001219;
  }

  ::selection {
    // The @supports function can let us use color-contrast() progressively
    @supports (background: color-contrast(#000 vs #fff, #eee)) {
      background: color-contrast(var(--article-color) vs #94d2bd, #005f73);

      /*
        Feel free to chain color-contrast() calls like this:
        background: color-contrast( color-contrast(var(--article-bg) vs #fff, #000) vs #94d2bd, #005f73);
      */
    }
  }
}

/* GLOBAL */
:root {
  --body-base: #fbf8cc;
  --color-primary: #94d2bd;
  --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: #000;
  font-family: "Barlow", sans-serif;
  font-size: 100%;
  letter-spacing: 0.25px;
  line-height: 1.75;
  margin: 0;
  padding: 0;
}

body {
  background-image: radial-gradient(
    circle farthest-corner at 108.9% 51.2%,
    var(--color-primary) 0%,
    var(--color-primary) 15.9%,
    #005f73 15.9%,
    #005f73 24.4%,
    var(--body-base) 24.5%,
    var(--body-base) 66%
  );
  block-size: 100%;
  display: grid;
  min-block-size: 100vh;
  place-items: center;
}

a {
  color: #c8553d;
  text-decoration: underline 1px dashed;
  text-underline-offset: min(5px, 1em);

  &:hover {
    color: #131313;
  }

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

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

section {
  inline-size: min(750px, 50vw);
}

.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-contrast(#000 vs #fff, #eee)) {
    display: none;
  }
}

              
            
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JS

              
                
              
            
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999px

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