Problem at customize SFSafariViewController preferredBarTintColor.

I am trying change SFSafariViewController Title bar color.

Following code to change a Title bar color.

vc.preferredBarTintColor = UIColor.blue

vc.preferredControlTintColor = UIColor.white

But displayed color is different.

Displayed color is 2425fe (red:36, green:37, blue:254)

Blue(UIColor.blue) is 0000ff (R:0, G:0, B:255)

why color is little Bright color?

Any help?