Sizing the width (pixels) of a dashboard - Layout card

Hi there,
I am building a wall tablet (Lenovo M10 plus) whic has if My data is correct a width of 1900 x 1200 pixels.
I am configuring my Dashboard with layout-card and mentions there is a total width of 1920 pixels, but then all cards are not filling in the width but I need to scroll left and right ?!?

views:
  - title: Home
    type: custom:grid-layout
    icon: mdi:home
    layout:
      grid-template-columns: 500px 500px 920px
    badges: []
    cards:
      - type: gauge
        entity: sensor.netpower
      - type: gauge
        entity: sensor.netproduction
      - type: gauge
        entity: sensor.hp_officejet_pro_9020_series_black_cartridge_2
      - type: gauge
        entity: sensor.hp_officejet_pro_9020_series_cyan_cartridge_2
      - show_current: true
        show_forecast: true
        type: weather-forecast
        entity: weather.maison
        forecast_type: daily
        name: AccuWeather

Instead, when I set my width around 1200 pixels, then all seems to fit.
When resolution says 1900 x 1200 pixels, 1900 is well the width being in landscape right ??