[Feat] Provide color values for deeply nested css variables

[phoenisx]

Is your feature request related to a problem? Please describe. Example CSS file:

* {
  --brand-hue: 0;

  --brand-dark1: hsl(var(--brand-hue), 0, 20%);
  --brand-dark2: hsl(var(--brand-hue), 0, 10%);

  --brand-light1: hsl(var(--brand-hue), 0, 90%);
  --brand-light2: hsl(var(--brand-hue), 0, 80%);
}

[color-scheme="light"] {
  --brand: var(--brand-light1);
  --brand-dark: var(--brand-light2);
}

[color-scheme="dark"] {
  --brand: var(--brand-dark1);
  --brand-dark: var(--brand-dark2);
}

Describe the solution you'd like Color for --brand CSS property is not getting parsed.

Current	Expected

[phoenisx]

The solution that I am working for now only works when the css variables are defined in sequence, i.e. css variable with color value should be defined before it being used, like in the description above, it won't try to find the value of the property recursively, which could be computation heavy.