Rule reminder
Invariable colors (never change): rosa (pink), viola (purple/violet), blu (dark blue), beige, lilla (lilac), arancio/arancione* (orange — arancione is variable: arancione/arancioni). Regular colors change: rosso/a/i/e, verde/i, blu is invariable but azzurro/a/i/e is variable.
Which color adjective IS variable (changes form)?