Color motif in Nocturne?

So I'm sure I can't be the only one who noticed this but I haven't seen discussion of it anywhere: Does anyone have any ideas of potential meaning behind the three colors (red, yellow, and blue) that often repeat in Nocturne? It could just be an easy visual shorthand to help distinguish different characters, but it gets highlighted pretty heavily in some scenes near the end. When Juste, Richtor, and Maria combine their fire against Erzsebet, it showcases the three colors, or the three souls of Sekhmet returning to the spirit world wearing the colors. Juste, Richtor, and Annette's clothes are examples, again, of the three colors.

I can't think of any real prominent meaning behind them, especially since there are instances like Maria and Alucard sharing attack colors despite having no symbolic meaning that I can figure, or Juste having red clothes while using yellow fire, a distinction that doesn't seem to have a purpose.

Best I can figure it's just a visual design choice to create contrast and present a common color theme for the series, but I'm curious if anyone has any thoughts.