I am usign gantry 5 with the preset two column-right preset. However the main content is overlapping the sidebar content. There is a .g-container styling in hydrogen_9.css on line 780 that is having a bearing on the width of the main content area and seems to be over-riding the section setting of 70% and 30%.
You can see it here
kmwebsitedesign.co.nz/gordonton/index.php/newsletters