Alteranitive to rolling a new theme for basic CSS edits?

Hi,
First off your plugin is great! I love the simplicity of it and yet how powerful it is, and the addition of CPT’s is very cool. My only request is to be able to drop my own custom stylesheet into my theme directory and have the plugin’s CSS be overwritten by my own. Is this possible?

Thanks again for the beautiful calendar solution.

https://www.ads-software.com/extend/plugins/wp-fullcalendar/