removing unnecessary margins

removed these margins as they are no longer necessary. Were used to provide space for left and right content areas within topic sections. These are only displayed now when in edit mode.
reduce font size in block region for large screens

leave font size intact for smaller screens
increase gutter width to 50px (25px padding on left and right)
compiled css changes
reduce border a little
Merge branch 'feature-course_better_block_division' into develop