I got your point, it due to the layout of this JA Mono template which divides the page into 2 sections:
Left block: CTA / Masthead content
Right block: displays the main content of a page
The width of right block is not enough to show all of the content you added into that page in T4 Builder.
In case that you want to have more width, I suggest you to narrow the left block so it can display better.