Custom:button-card styles icon and card reaction to each other. Intended or bug?

So i was making a desktop page for energy and i wanted the Amperage value to color code according to its value.
I tested the code for the card itself and then noticed the icon part would follow. But only if i put in a icon: followed by a - color: in the styles section. without it it would do nothing.

type: vertical-stack
cards:
  - type: custom:button-card
    name: Energy Usage
  - type: horizontal-stack
    cards:
      - type: custom:button-card
        icon: mdi:current-ac
        layout: icon_name_state
        entity: sensor.current_phase_l1
        name: L1
        show_state: true
      - type: custom:button-card
        icon: mdi:current-ac
        layout: icon_name_state
        entity: sensor.current_phase_l2
        name: L2
        show_state: true
        styles:
          icon: 
          - color: 
          card:
          - color: >
              [[[
                if (entity.state >= 1 && entity.state <= 4 ) return 'green'
                else if (entity.state >= 5 && entity.state <= 8 ) return 'yellow'
                else if (entity.state >= 9) return 'red'
                else return 'rgb(225,225,225)'
              ]]]

energy

Could i code further buttons like that (in custom:button-card) or is it a bug and might get changed?

Use color_type: card :

        type: custom:button-card
        icon: mdi:current-ac
        layout: icon_name_state
        entity: sensor.current_phase_l2
        name: L2
        show_state: true
        color_type: card
        styles:
          card:
          - color: >
              [[[
                if (entity.state >= 1 && entity.state <= 4 ) return 'green'
                else if (entity.state >= 5 && entity.state <= 8 ) return 'yellow'
                else if (entity.state >= 9) return 'red'
                else return 'rgb(225,225,225)'
              ]]]

[/quote]

Additional infos can be found here: GitHub - custom-cards/button-card: ❇️ Lovelace button-card for home assistant