center my homepage content using twenty seventeen theme and tablepress plugin

Dear Sir,
I put all the contents of my homepage in a tablepress table and i tried to center it.
But it’s not working because my left sidebar menus and page contents appear to be on the left side while right sidebar is shown to the very right side while viewing in a big desktop screen or laptop screen. How can I make all the contents appear in the center rather viewing it at both sides?
Thank you for the help.
Jyothi

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