Card-mod remove border outline

Hi All,

does anyone know how to get rid of the outline ob the button cards?
image

  - type: custom:button-card
    tap_action:
      action: navigate
      navigation_path: /dashboard-phone/hidden-car-security
    hold_action:
      action: none
    color_type: card
    color: none
    styles:
      card:
        - height: 27px
        - width: 27px
        - '--ha-card-background': rgba(0, 0, 0, 0.0)
        - box-shadow: none
    style:
      bottom: '-1%'
      left: 12.3%

thank you everyone