Layout problem

Hi,

I’ve been spendings hours of research but can’t find any solution.
I think a picture says more than words.

This is what i have:
When i make a grid i the second column, the first column expands to the same height as the first.
How can i avoid this ?

and this is what i want (i painted the grey area out):

This is the testcode i actually using:

kiosk_mode:
  non_admin_settings:
    kiosk: true
    ignore_entity_settings: true
views:
  - title: Huis
    path: huis
    type: custom:grid-layout
    layout:
      gridrows: auto auto
      grid-template-columns: 70% 30% 
      grid-template-areas: |
        "a1 a2" 
        "b1 b1" 
    subview: false
    theme: clear-dark
    badges: []
    cards:
      - type: entities
        entities:
          - sensor.sun_next_dawn
          - sensor.sun_next_dusk
          - sensor.sun_next_midnight
        view_layout:
          grid-area: a1
      - square: true
        type: grid
        cards:
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.buitenverlichting
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.buitenverlichting
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.buitenverlichting
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.buitenverlichting
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.hue_color_spot_4
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.hue_color_spot_4
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.hue_color_spot_4
          - show_name: true
            show_icon: true
            type: button
            tap_action:
              action: toggle
            entity: light.hue_color_spot_4
        columns: 3
        view_layout:
          grid-area: a2