Storefront theme question

Hello.
I’m building my 1st site ever in WordPress using Woocommerce and Storefront theme.
I have manage to arrange almost everything but i can’t found how to wide my page by disabling the huge red marked gaps in left and right.
Site not yet published so her eis the pic http://img159.imagevenue.com/img.php?image=60556_wordpress_122_572lo.jpg

Thank you in advance!!!