Stronger Colors

I would not assume "pessimism" by this usage.

In the first sentence, "darker" suggests "sinister" (less honest or open or for bad motives). So "dark" is okay.
If you mean something else, what do you want to say?

In the second sentence, there is a contradiction between "dark" and "alive."
Do you want to say that the colors are dark (in shade) but also alive (not dull)?

1_ Just like darker colors that are faster and easier seen by the eyes, I want to say the UK is more "active" in case of foreign policy, I don't want to transfer a "sinister" meaning.

2_ thanks for suggesting "rich", I think that's what I was after. So do you mean dark colors are different from rich colors? Before, I've learned that if a color, say red, is stronger and more filled with th

mojtaba vahdati I want to say the UK is more "active" in case of foreign policy

Then that's what you need to say. 'Darker' doesn't work.

Yes, darker colors are the shades that approach black while lighter colors are those that approach white. You can call them rich (meaning there is more of that color). But at a certain point, the red is going to darken and, I would think, lose what I would call its richness.

The color blue is actually stronger than yellow, red or any light color, but is this just blue. no its actually any color that is dark will be stronger as they are colder color which to a degree is actually colder which cold particals are stronger. so to a very little extent you could say darker color have more strength than lighter ones this is a proven by scientist.