<h1>My text color is defined by a custom property</h1>
:root {
  --text-color: rebeccapurple;
}

h1 {
  color: var(--text-color);
}

External CSS

  1. https://codepen.io/piccalilli/pen/e691135733d812201da5d9de1fc5eab4.css

External JavaScript

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