Overriding CSS for modules

Hello,

For some reason, most of the font families and sizes don't jive with my theme, so I am having to override most of easysocial theme so that they inherit my theme's font classes. I've successfully done this for the component styles but can't seem to make the module overrides work. I've tried saving my style.css sheet in both theme/html/com_easysocial/styles and theme/html/module_easysocial_stream/styles to no avail. PLease let me know the correct way to do this.