Theme: Dark Arts, How to edit the css of the graphic view?

Hello everyone!.
I downloaded the Css of this beautiful theme, but the colors in the graphic view appear gray and not red as they are supposed to appear. So my question is how can I customize the color so that it looks similar to that theme?

This is the link of the sample theme of Graphic view

And here below the images of the corresponding theme with the graphic view

But my graphic view does not appear to me with the colors of the previous images, it appears like this:

Could someone guide me and help me with the color of the graph view? to make it red like the sample images?

The Dark Arts graph with me is grey too. You could try to contact the person who made it, although I am not sure if they will reply. I contacted him/her a few weeks ago and am still waiting for a response.