What happens to city lights within earth atmosphere that makes stargazing difficult?

City lights create light pollution, which scatters and diffuses artificial light in the atmosphere, obscuring the visibility of celestial objects. This excess brightness makes it challenging to see fainter stars and other astronomical phenomena, as they are drowned out by the glow from urban areas. Additionally, atmospheric particles can further scatter this light, reducing clarity and contrast in the night sky. As a result, stargazing in urban environments is often less rewarding than in darker, rural areas.