I have not messed around with themes much yet, but I would really like to be able to adjust the relative width of different blocks in my Bartik theme. As you can see in the screenshot, my panel is not quite big enough to display both views without overlapping, and there is plenty of extra space on the sides.
How does one change the relative widths assigned to each block? Also, when I start making changes like this, would it be wise to make my own copy of Bartik and store it elsewhere?