Changing column widths

I've just installed the NELO theme and I am having trouble with the column widths on the home page. I am using the Timely calendar plug-in on the widgetized right box area for the home page. What's happening is that the calendar items are bleeding into the white space. I was hoping I could adjust the column width of the intro column which is the left of this area to accommodate. Or I'm open to other options as well. Thanks.