Hi,
It looks like a triple split. We don't have that. What you can do is to use
2 splits, but the behavior will not be the same, the other two splits will
occupy the space proportionally and the first division will move. Something
like:
IupSplit(IupSplit(box1, box2), box3);
Each box could be:
Open this pen: https://codepen.io/chriscoyier/pen/zYvoQEQ and resize the
result panel to see the effect.
(I am assuming Editor View with the result full height and html/css/js stacked
on the left or right.)
The four (blank/grey) aside/sidebar-module boxes should at some point jump to
below
