Need Help W/CSS Code in Additional template

[HM666]

I'm trying to edit the editor on a skin that I plan on putting in my skin shop. Its a dark skin so the white or light borders and backgrounds inside the drop down is not suitable for what I'm doing.

I'm able to edit the editor.css file and change the CSS I want to change to make the borders/backgrounds dark, but when I add the code into the additional.css template and even include !important in the code it will not show properly on the skin. For obvious reasons its not optimal to have this code in the editor.css file since this skin will be redistributed. The css code that does change the borders is...

.cke_panel_listItem a {
padding:2px;
display:block;
border:1px solid #000000!important;
color:inherit!important;
text-decoration:none;
overflow:hidden;
text-overflow:ellipsis;
}*

I've tried many different variations, I've tried just using

.cke_panel_listItem a {
border:1px solid #000000!important;
}*

as well both have not worked once I have placed the editor.css file back with the default values. What do I need to do besides changing the code in the editor.css to get this to render properly in the additional.css template?