Is there ways to reduse the dark color around that area ?
You sound fine. Vulvas are like snowflakes - all are different, and all are beautiful. They vary widely in terms of size, shape, color, and texture. Colors range from solid black to purplish to grey to brown to palest pink, and all are perfectly normal :-)
However, if this is a brand NEW color change, you may want to check it out with your doctor, just to be sure.
I think it's OK that the are is dark. As long as you are not experiencing any pain, itching, or odor you are probably OK.