Dave,
You won't be able to change that style. It's embedded by the Like button and not something they let you alter. The following 2 changes to your template CSS will fix the problem. Right now, there's a few settings of "overflow:hidden" on your main content area container.. that prevents any overflow from happening. Usually a good thing, but in this case, you want overflow.
In your templates/paradigm_shift/css/template_default.css file around line 65, you'll see the definition for #s5_columns_wrap with a setting of "overflow:hidden;" Comment out that line:
At line 79, you'll see the definition #s5_center_column_wrap_inner. It has the same overflow definition. Comment it out like above.
That should get you going, but if not (or it causes other issues, which it shouldn't), let us know!
Alex