To make integrating with your front-end easier, we decided to have the CDA returning a handy string containing the rgb() functional notation of a color field, expressed with the current standard syntax.
As an example, the following query:
{leaf {color {cssRgb}}}
Returns a string containing three space-separated values, representing respectively values for red, green, and blue. Optionally, it may also include a slash / followed by a fourth value, representing alpha.
{"data": {"leaf": {"color": {"cssRgb": "rgb(213 185 185 / .43)"}}}}