Colour of Back Button in Navigation View

[kenono]

I'm using a navigation view in my application, which has a black look throughout. My issue is that the back button within my color scheme is not at all very distinctive, it's hard to see the outline of the button itself. Indeed, the bottom half of the button is barely visible (see image).

IMG_0393.PNG
I can't seem to figure out the SASS variable or CSS needed to change the colour of this button, or to make it more distinct.
My question is how may I make this button more visible?

This is some of the relevant SASS code I have for my application:

$body-bg-color: #000; 
$base-color: #000;
$base-gradient: 'glossy';
$toolbar-gradient: 'glossy';

[mitchellsimoens]

I would create a new ui based on the back ui in SASS. You can configure what the back button via the backButton config on the navigationBar config on the navigation view.