Red and yellow and pink and green; purple and orange and blue—no, we're not singing the “Rainbow Song” from preschool, we're describing all of the fashion colors you have applied over the past couple months! The hottest sensation in coloring is all about painting those vivid pastel highlights or colorful base blends. For this BTC member, it was just another one of her clients wanting some vivid streaks on her ends. Unlike most clients, however, this one was 11 years old, and her mother wanted assurance that these fashion colors would last. “We agreed on $75, just so…