Aligning Tabs - No background - Storyline 2

I have created 4 tabs on a page after viewing the tutorial in Storyline 2 (brand new user).  In the tutorial, the page had a background, so that the tabs section on the left already had a defined space. 

I do not have any kind of background on the right side of my page, but I still need to make my 4 tabs be of equal width and positioning on the page. As it is now a couple of them are off by a millimeter (horizontally) and I  *can not* make them align with the other tabs. 

Here's a rough idea of what I mean

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Thanks in advance : )

Heather