Allocating uneven widths to cards

I am trying to allocate 2/3 of the width of a lovelace card to one card and 1/3 to the other. As you can see in the first picture when the browser window is wide enough, there is no issue and the cards are displayed correctly. When the windows is narrowed, the card enters the adjacent card.
Also, in the app, if you look closely, the gap that is present between the disk and the uptime card on desktop is not there.
Is there a way to fix these?

Here is my code for this portion:

type: vertical-stack
cards:
  - type: horizontal-stack
    cards:
      - type: 'custom:mini-graph-card'
        entities:
          - sensor.processor_use
        name: CPU
        icon: 'mdi:chip'
        animate: true
        line_width: 10
        smoothing: true
        line_color: '#0277BD'
      - type: 'custom:mini-graph-card'
        entities:
          - sensor.memory_use_percent
        name: RAM
        icon: 'mdi:memory'
        animate: true
        line_width: 10
        smoothing: true
        line_color: '#ff1744'
  - type: 'custom:layout-card'
    layout: grid
    grid-template-columns: 33% 33% 34%
    cards:
      - type: 'custom:mini-graph-card'
        gridcol: 1 / 3
        entities:
          - entity: sensor.disk_use_home
            name: Disk
            smoothing: true
          - entity: sensor.disk_use_percent_home
            show_state: true
            show_graph: false
        icon: 'mdi:sd'
        line_width: 5
        animate: true
        hours_to_show: 100
      - type: sensor
        entity: sensor.uptime_parsed
        gridcol: 3 / 3

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