Why is my Panel doing this?

Lake_Country_GIS

I have been working on refining my custom widget and would like it to function similarly to that of the Jewelry Box theme in that there is a side panel that can be minimized and maximized by a small tab. 

For whatever reason the map shifts and takes my panel with it separating it from the sidebar? How do I anchor my panel to my sidebar? This is a custom theme I created for my project.

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