Child theme requires "!important" to inherit

I’ve been told that my code is very messy and that I don’t understand the coding hierarchy. (Uhm. Guilty!) I never expected theme customization to be this difficult and it is not my forte at all. I would really like to clean up my code and improve load speeds but I’m at a loss. It seems like consistently the only way to get my child theme to override its parent is to use “!important” in the child style sheet. I know this isn’t right but it did the job in a pinch before. It’s weird that it will see the child theme’s commands but only if I push the issue. Is there something I am missing that is making me having such an “overbearing parent” theme? ??

My site is here.