I checked your site and it seems that you have already resolved these issues.
To adjust the space between columns, you also need to adjust the width of the columns.
I can see you have added
margin-right: 0.5%;width: 25%; to the left column and added
margin-left: 0.5%; to the right column.
I could also not see the grey background color of the column that is visible above the image.
Can you please confirm if where to resolved these issues, if not kindly provide us with screenshots.