Are there any laws and regulations in the current country that stipulate that the architectural appearance of the property community must be unified? If so, which rule is it? thank you

There is definitely no provision in the law. In the property management regulations, maintaining the uniform appearance of residential buildings is actually a way to preserve and increase the value of owners' property. If the appearance of a community is clear and refreshing, the grade of the whole community will go up, and the house prices will sell better in the future. Otherwise, you can do whatever you want. I paint the color, and finally the exterior wall looks like camouflage. Will you choose this community to buy a second-hand house in the future?