Hai i capelli biondi! in the singular and Avete i capelli biondi! in the plural are Italian equivalents of the English phrase "You have blond hair!" Context makes clear whether one "you" (case 1) or two or more "you all" (example 2) suits. The respective pronunciations will be "eye ee ka-PEL-lee BYON-dee" in the singular and "a-VEY-tey ee ka-PEL-lee BYON-dee" in plural in Italian.
"Blonde hair" in English is capelli biondi in Italian.
"Unique hair" in English is capelli unici in Italian.
Capelli.
Capelli neri is black hair in Italian
"I have short black hair" in English is Ho i capelli corti neri in Italian.
You say "capelli lunghi".
Bruno in Italian means "Bruno" as a name and "(a person with) dark brown (hair)" in English.
"Secret hair" is capelli segreti for hair on one's head and peli segreti for elsewhere on the body in Italian.
Lunghi capelli neri.
Bella Roux hair salon, in mixed French and Italian means "Beautiful Redhead" in English.
Capelli sensuali is an Italian equivalent of the English phrase "sexy hair." The masculine plural noun and adjective also translate into English as "sensual (sensuous) hair." The pronunciation will be "ka-PEL-lee sen-SWA-lee" in Italian.
ragazza bruna. if you use "castana" is better.