Single Vertical Stack, Centered, 60% width

Is there really no way to just get a single vertical stack in the center of the screen with a specified width? I can put a single vertical stack on a Masonry layout but I can’t figure out how to control the width. What I do is a grid layout card with 20% 60% and put a dummy vertical stack in the first column, but REALLY? THIS is what I have to do?

On a related note, I finally figured out how to make some dashboards responsive so that they display well on both my Mac and my iPhone. This is the magic:

 - type: custom:layout-card
   layout_type: custom:grid-layout
   layout:
     grid-template-columns: repeat(auto-fit, minmax(130px, 1fr))

Try the new sections view type. It is possible with that.