Horizontal top pane resizing

[Jv650]

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Horizontal pane resizing

Been trying to solve this issue for the past day and can't seem to find any helpful leads. Everything works just fine BUT, whenever I try to adjust the horizontal pane it adjusts the bottom pane instead. So essentially, the bottom pane is overlapping the top pane if i adjust it up.

Solution or assistance I would appreciate

I would like to be able to re-size similarly to how the vertical pane resizes all three panes. Some context: I have one vertical pane and horizontal line dividing my other two panes. I want the divider line to resize/adjust the panes up and down simultaneously.

Describe alternatives you've considered

I'm new to programming so if this is not possible let me know. Thank you!