On larger screens, containerd causes significant wastage of space on both sides, and it seems that removing it also doesn't affect the display outcome on smaller screens. The first screenshot shows the display effect with containerd, while the second one is the result after I removed containerd.
This is what I referred to as "containerd."
Comment From: philwebb
We have a plan to migrate the docs to Antora (see #33766) which should fix this. I'm not keen to make changes to the exiting CSS since it will ultimately be replaced.