The woocommerce product page (for a single product, which has the picture, description, and an add to cart button) doesn’t fill the “CONTENT” section from left to right.
Instead, there is a generous “margin” on the left and right that allow the body background image to show through.
All other pages of Woocommerce, as well as all other blogs, are filling the content left to right completely.
It’s like there is some “limit” on the width of the woocommerce single product content, or somehow a “margin-left and right” are getting set for that particular page only.
I’ve included a link to the affected page. The “starry night background” image is showing left and right within the site-container “golden” border” wrapper. The content panel should go wall to wall like all other blog pages do.