Louis Vuitton brown monogram?

I am considering buying myself a new LV bag for Christmas and I am confused about something. I looked at louisvuitton.com and eluxury.com and it looks like some of the bags in the same line have different colors. For example, the brown monogram Popincourt Haut bag appears to be a very dark brown with greenish LVs while the Speedy bags appear to have more of a reddish brown background with golden colored LVs. Are they supposed to be like this?