Background Image Not Displaying

Under "theme options" > "general" > "add media" I tried adding a background image but it does not display when I view the website. In another post Damiano said "For who has Uncode version 1.0.4 or earlier please modify row #77 from: [some code to some other code]", however he doesn't say in what file. Can you please tell me how to fix this problem and/or in what file I can access the "box-wrapper" class div?

http://www.muninnweb.com/
Version 1.0.4