Separate CSS for Map icons

I’ve been trying to change the colour of my map icons in a custom theme (slate) but the icons seem to share the same css as primary-text-color therefore if I want to change the icon colour everything else that references primary-text-color also changes. See the following post for a description of the issue and a partial solution: How to change map icon

My suggestion it to add a map-icon-color css entry so that is can be individually changed.

Thoughts?