🔹 Layout-card - Take control of where your cards end up

[CDRX2]

This works for me to remove the margins using card-mod:

    type: 'custom:mod-card'
    card_mod:
      style: 
        layout-card$: 
          grid-layout$: |
            :host {
              padding: 0px !important;
            }
            #root {
              margin: 0px !important;
            }
            #root > * {
              margin: 0px !important;
            }
    card:
      type: 'custom:layout-card'
      layout_type: grid
      layout_options:
        grid-template-rows: 100%
        grid-template-columns: 25% 75%
        grid-gap: 0

A bit different, though, since I’m using a layout-card.