Studio theme adminbar.css

I am trying to change the colours of the sliding admin/login section of the Studio theme. I am not sure how I set up the child stylesheets to override the adminbar.css

I have tried copying the adminbar.css to my child theme folder (using the updated section to change the colour of the sliding panel background only) and creating an import line in the childs style.css

When I view it using firebug this child level adminbar.css is overriden somewhere else. I am not sure how I should be doing this. Can you help please?