Icon_color in mushroom card not working

Folks,

I cannot for the life of me figure out this absolutely basic thing. I simply want to change the icon and brightness bar of the mushroom light card which is supported by the mushroom cards but it will not work. Here is my yaml:

type: custom:mushroom-light-card
entity: light.front_foyer_pendants
show_brightness_control: true
icon_color: gold
card_mod:
  style:
    mushroom-card .actions mushroom-light-brightness-control$: |
      mushroom-slider {
        --main-color: gold;}
      }

Here is the error:

Visual editor is not supported for this configuration:

At path: icon_color -- Expected a value of type `never`, but received: `"gold"`
You can still edit your config in YAML.

This is simple but I cannot figure out what is causing this not work.
Thanks in advance for the help!

Hello, did you find a solution?

No I gave up on it.