Let Nav block dropdown arrow inherit the colour of the menu item by default

It will be great if the dropdown arrow inherits the colour of it’s menu item by default. This would allow us to specify a default style, a hover style and a current style and the arrow would adapt depending on the state of the item.

Example of ideal end result:

Currently it seems to stick to the default regardless of state:

If there is a built-in solution to this already, please let me know.

Thank you!