is there a way to set the content margins so that i can see more of the background iamge?
The max width should be 1170px so anything beyond that will show the background. Are you asking how to reduce the max width of the main site container?
the max width of the site container
Whenever you want to change the style of any part of the theme, use
Chrome or Firefox+Firebug and right click on the area you want to change
and choose Inspect Element. That will bring up a console that shows
exactly which lines of CSS in exactly which files affect that element so
that you can go in and change the style how you see fit.