Plugin for generating color scales.

npm install postcss-color-scale

From the command line:

post-css --use postcss-color-scale styles.css -o styles.out.css

This can be used with postcss-cli in a npm run script. Great example post

:root {
  --cs-color: blue;
  --cs-variance: 20;
}

body {
  background-color: cs(-1);
}

:root {
  --cs-color: blue;
  --cs-variance: 20;
}

body {
  background-color: #0000CC;
}

You can define any name for your color as long as you prefix the custom property with --cs- it will be available as the second argument to the cs() function.

:root {
  --cs-primary: blue;
  --cs-secondary: red;
  --cs-tertiary: green;
  --cs-variance: 20;
}

body {
  color: cs(-1, primary);
  background-color: cs(1, secondary);
  border-color: cs(2, tertiary);
}

:root {
  --cs-primary: blue;
  --cs-secondary: red;
  --cs-tertiary: green;
  --cs-variance: 20;
}

body {
  color: #0000CC;
  background-color: #FF3333;
  border-color: #66E666;
}

The way the scale works is you supply a color and a variance ( meaning the difference between steps ) then use the cs() function in your stylesheet to get a step of color from the scale. Positive numbers go up the scale giving you a lighter color while negative numbers go down the scale giving you a darker color; where zero is the base color. cs(0) will give you the base color. cs(1) will give you a lighter color and cs(-1) will give you a darker color.