caraya/index.html

## index.html
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .box {
      height: 100px;
      width: 100px;
      border: 5px solid #000;
    }

    .rp {
      background-color: var(--color-rebeccapurple);
    }

    .magenta {
      background-color: var(--color-magenta);
    }

    .red {
      background-color: var(--color-red);
    }
  </style>
</head>
<body>
  <div class="box rp"></div>
  <div class="box magenta"></div>
  <div class="box red"></div>

  <script type="module">
import Color from "https://colorjs.io/dist/color.js";

function processColor(name, color) {
  let myColor = new Color(color);
  let cssColor;

  if (CSS.supports("color", myColor)) {
    cssColor = myColor.toString();
  }

  // Check if the browser supports the display-p3 color space
  // if it does then convert the color to that color space
  if (CSS.supports("color", "color(display-p3 0 0 0)")) {
    cssColor = myColor.to("p3").toString();
  }

  if (CSS.supports("color", "lch(0% 0 0)")) {
    cssColor = myColor.to("lch").toString();
  }

  let root = document.documentElement;
  let colorName = ('--color-' + name).toString();

  let registeredColor = root.style.setProperty(colorName, cssColor);

  return registeredColor

}

processColor('rebeccapurple', '#663399')
processColor('magenta', '#ff00ff')
processColor('red', '#ff0000')
</script>
</body>
</html>
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<style>
	.box {
	height: 100px;
	width: 100px;
	border: 5px solid #000;
	}

	.rp {
	background-color: var(--color-rebeccapurple);
	}

	.magenta {
	background-color: var(--color-magenta);
	}

	.red {
	background-color: var(--color-red);
	}
	</style>
	</head>
	<body>
	<div class="box rp"></div>
	<div class="box magenta"></div>
	<div class="box red"></div>

	<script type="module">
	import Color from "https://colorjs.io/dist/color.js";

	function processColor(name, color) {
	let myColor = new Color(color);
	let cssColor;

	if (CSS.supports("color", myColor)) {
	cssColor = myColor.toString();
	}

	// Check if the browser supports the display-p3 color space
	// if it does then convert the color to that color space
	if (CSS.supports("color", "color(display-p3 0 0 0)")) {
	cssColor = myColor.to("p3").toString();
	}

	if (CSS.supports("color", "lch(0% 0 0)")) {
	cssColor = myColor.to("lch").toString();
	}

	let root = document.documentElement;
	let colorName = ('--color-' + name).toString();

	let registeredColor = root.style.setProperty(colorName, cssColor);

	return registeredColor

	}

	processColor('rebeccapurple', '#663399')
	processColor('magenta', '#ff00ff')
	processColor('red', '#ff0000')
	</script>
	</body>
	</html>