Currently I'm working on creating an interface for a web application. The main menu is at the top, a sub-menu is collapsible on the left side and another collapsible bar (pretty thin) on the right side. This setup leaves a lot of space on large screens in the middle area. We have a few views that consist out of a list with items the users create themselves.
Now the thing is that the rows in the list do not have a lot of information in them and if I stretch it over the whole horizontal space between the left and right menu it looks pretty silly (little information scattered very spacious).
How can I handle a situation like this best? Is the best practice here to stretch it, only use part of the available space and leave the rest empty or are there other options?