When you use more than one adjective to designate a single color (like "light blue," "dark green," "pale pink" etc.), neither of the adjectives changes according to the noun it modifies. For example:
Il a les yeux bleu clair et les cheveux brun foncé.
"He has light blue eyes and dark brown hair."
I thought is was because most colours are masculine and the adjectives were describing the colours (for example dark red boots is saying the red is dark, and the boots are red, not the boots are dark and red, though technically they mean the same thing). I could be wrong though, I'll have to search it up.
When used as an adjective (as in "elle porte une jupe rose clair"), the color word is an adjective and it does not have a gender by itself. As it happens, the color "rose" (FR) is invariable in regard to gender anyway and when used as a compound color term (light pink = rose clair), there is no agreement at all with the noun to which it refers. If you use the color as a noun, then it has a gender, e.g., Some little girls love to wear pink = Certaines petites filles aiment porter du rose. (WordReference)
I was a little confused as well but I think that "rose"(pink) and 'clair' (light) stay the same because they are two adjectives describing one word and apparently when other feminine nouns are being described by two adjectives, they stay masculine like the examples that 'Ripcurlgirl' gave above, "bleu clair" and "brun foncé"!
Dual adjectives that designate a single colour always remain masculine and singular regardless of noun gender or plurality.
BTW, rose (the colour pink) is an invariable noun when it comes to gender but it does take the plural when used alone e.g. Les chaussures roses → The pink shoes.
While "light pink skirt" makes more sense, I just learned clair=clear. So I answered "She is wearing a clear pink skirt" and it was marked wrong. Can clair can mean both light and clear? How do you know when it means one or the other, and if both are correct, "clear" should not be marked wrong?
Clair(e) can mean light/bright, clear, transparent, or be a quality of clarity, such as "a clear explanation" → une explication claire. Whenever it is used in unison with another adjective to designate a single colour it always in the masculine singular - clair - and always means "light".
Hello! I'm assuming that because the translation of "rose" from French to English is "pink", it probably thinks that you're using the French word "rose", instead of how "rose" can also mean "pink" in English, and it is expecting you to use "pink" when translating. If that makes sense?
If I'm wrong, someone please correct me :) Thanks!
Actually, in an earlier color lesson I was marked wrong for using pink; the correction was rose! rose = rose in that lesson.