Question: how to set colour based on light brightness

Hi,

I have a button that I want to be “background” colour" when off and “yellow” when at 30% (which is the tap_action of this button).

…I know this isn’t a bug, but I am not sure where I can post a question like this.

Below is the best I have got and I know it is wrong. Can anyone advise"

          - type: 'custom:button-card'
            entity: light.hallway
            color: auto-no-temperature
            color_type: card
            state:
              - value: "off"
                color: var(--paper-item-icon-color)
              - value: {{state_attr('blight.hallway','brightness_pct')}}
                operator: "="
                value: 30
                color: yellow
            styles:
              card:
                - height: 100px
            name: "Low"
            tap_action:
              action: call-service
              service: light.turn_on
              service_data:
                entity_id: light.hallway
                brightness_pct: 30

[RomRider]

Happy that it works. I’m going to close this, then 😃

[JCHH2]

agh, I posted on reddit, not here