Row Properties will allow you to customize things like the background color, background image, etc., within a row.
To edit a row's properties, click on the area to the left or right around a row that has been added to your template or marketing piece:

Once you have selected your 'row', you will find ROW PROPERTIES appear along the right:

Unlocked/Locked: This will allow you to lock down content for your agents. If the lock is enabled, agents will not be able to edit this content. If left unlocked, agents will be able to edit the row to add their own content.
Row background color: This will allow you to adjust the background color of the full row, stretching to the widths of the row.
Content background color: This will allow you to adjust the background color restricted to the content area. To help visualize this better, please feel free to apply a different color to the row and content to see each area that will be affected.