Question about css & using !important to overwrite styles

I have been using the GF forms for quite some time. Recently I had to do quite a bit of css work for a project and I found myself adding !important after almost every css class declaration in my style.css stylesheet so that it would be rendered instead of the default classes. Is there a place I should be declaring these custom css rules so that I don't have to declare an !important after each one. It becomes rather tedious. I usually start with the default css as a base and work from there so I can maintain the basic form styles which come packaged with GF for standards compliance.