@media screen and (max-width: 1680px){
    .head .left {
        width: 700px;
    }
    .head .left li {
        margin-right: 21px;
    }
    .head .right {
        width: 490px;
    }
    .announcement li {
        width: 400px;
    }
    .announcement li span {
        width: 310px;
    }
    .announcement li {
        margin-right: 10px;
    }
}
@media screen and (max-width: 1440px){
    .announcement>p {
        font-size: 26px;
    }
    .announcement li p {
        font-size: 16px;
    }
}