@media screen and (width<=1200px) {
    .cloud3,.cloud2{
        display: none;
    }
    .star16, .star15{
        display: none;
    }
    .moon7, .moon6{
        display: none;
    }
}

@media screen and (width<=1000px) {
    .star{
        transform: scale(0.7);
    }
}

@media screen and (width<=768px) {
    .cloud3{
        display: none;
    }
    .moon7{
        display: none;
    }
}