Space Between Containers

Good Evening,

How can I eliminate the horizontal white space between between several containers with different background colors? No pages are live, still in draft.

For example, I would like the blue container to touch the red container without a horizontal white space between them. The containers are primary meaning not nested within each other. I do not have any margin or padding applied. I went into appearance > customize > container. I have width on 2000px and everything else is 0. The content layout box is currently set to "Separate Containers". It didn't seem to effect anything when I changed to "One Container".

The containers are set up:
Container - Blue Background
H2 - (inside container)
H2 - (inside Container)
Container - Red background
H2 - (inside container)
H2 - (inside container)

Thanks for your help.

Darin