It appears that you are previewing the website from inside the Customizer. I recommend previewing the website from mobile as it is published since the preview will be different without the BoldGrid Customizer view. For instance, the editing buttons will not be present and the responsiveness of the theme will behave more appropriately.
Okay so after playing with the theme we have discovered the bottom footer text line was to long and creating extra space even in mobile. After shortening the text line the problem went away.