Left justification of menu items has changed to center justification

Hi –
I have not made any changes to the menu, so something must have changed in a theme update. My drop-down menus are all left-justified by default. For some reason, the 2nd level menu on the home page (under the top-level “Go Deeper” is now center-justified. See attached file “Screen Capture 1.png”. It should look like the attached “Screen Capture 2.png”.

Can you please help me fix it?

Thanks,
Kat Willson