卡通扁平化手绘风多元人群不同年龄性别友好微笑打招呼

illustration, 16 characters, children, teenagers, adults, middle-aged, elderly, various hairstyles, glasses, expressions, clothing, smiling, actions like waving, touching hair, formal shirts, casual T-shirts, no interaction between characters, each character framed by a circular background, simple background design, soft yellow, blue, green color scheme, clean and bright visual effect, friendly and positive emotion, diversity and inclusion, cartoon style, soft colors, detailed