Make two colour - one light and one dark

two_colours.R

f1 <- sample(0:255,3)
while (sum(f1*c(0.2126,0.7152,0.0722)) < 0.85*255) { # brightness
  f1 <- sample(0:255,3)
}
f2 <- sample(0:255,3)
while (sum(f2*c(0.2126,0.7152,0.0722)) > 0.15*255) { # brightness
  f2 <- sample(0:255,3)
}

if (runif(1) > 0.5) {
  farve1 <- rgb(f1[[1]], f1[[2]], f1[[3]], maxColorValue = 255)
  farve2 <- rgb(f2[[1]], f2[[2]], f2[[3]], maxColorValue = 255)
} else {
  farve2 <- rgb(f1[[1]], f1[[2]], f1[[3]], maxColorValue = 255)
  farve1 <- rgb(f2[[1]], f2[[2]], f2[[3]], maxColorValue = 255)
}