I think if it is cotton-padded jacket, it is certainly the most environmentally friendly, because sewage will be discharged during the dyeing process. Cotton has white and colored cotton. I prefer white when I buy clothes. Although my lucky color is gray, I still try to buy light clothes, which are more environmentally friendly than dark clothes. Then, in terms of materials, natural materials such as cotton, hemp and wool are the most environmentally friendly, and chemical fiber is definitely not. It is extracted from petroleum and will pollute the environment.