this generally happens because an element on the page has been given padding or some odd margins and is quite common with page builder content. Its generally better to find the elements causing the issue and correct them but that can be painstaking… the easier fix is to use this CSS:
Hmmm, tried that and no luck. I’ve already worked out the cause actually, it’s the sidebar featured post widget. However much I tweak the width of that widget or play with the GP container dimensions, I can’t remove the issue. Any more ideas?