I am fairly new to OBIEE and I am attempting to format my heading to add a dashed border rather than a solid border. I attempted to do so using the following settings:

However, the border ends up being applied around the cell content (the heading name text) rather than heading cell border, so it's not really a border, but a text outline. I don't have this issue if I don't apply the Custom CSS Style and the border reverts to being around the cell rather than around the cell content.
Sample

Am I using the right Custom CSS Style syntax? Please let me know.
Thanks in advance for your help.
James