Hi Mike,
If its any help to you here's the css overrides I use for responsive framework skinning and it usually works:
#ControlBar, #ControlBar:before, #ControlBar:after, #ControlBar *:before, #ControlBar *:after,
#ControlBar li, #ControlBar li:before, #ControlBar li:after,
#ControlBar a, #ControlBar a:before, #ControlBar a:after,
.dnn_mact, .dnn_mact:before, .dnn_mact:after, .dnn_mact *:before, .dnn_mact *:after,
.dnn_mact li, .dnn_mact li:before, .dnn_mact li:after {
-webkit-box-sizing: content-box !important;
-moz-box-sizing: content-box !important;
box-sizing: content-box !important;
}
.navbar-default .navbar-nav > li > div > ul > li > a, .navbar-default .LoginLink {
color: #ffffff;
}
.navbar-default .navbar-nav > li > div > a:hover,
.navbar-default .navbar-nav > li > div > a:focus,
.navbar-default .navbar-nav > li > div > ul > li > a:hover,
.navbar-default .navbar-nav > li > div > ul > li > a:focus {
color: #ffffff;
background-color: #178acc;
}
Give it a go to see if it solves your problems,
Regards,
Geoff