媒体查询

<meta name="viewport" content="width=device-width, initial-scale=1"/>

@media only screen and (max-width:639px)...

@media only screen and (min-width: 1080px) and (max-width: 1300px) {
    html {
        font-size: 8.32px;
    }
}

@media only screen and (min-width: 1300px) and (max-width: 1580px) {
    html {
        font-size: 11.38px;
    }
}

@media only screen and (min-width: 1580px) and (max-width: 1900px) {
    html {
        font-size: 13.29px;
    }
}

@media only screen and (min-width: 1900px) and (max-width: 2560px) {
    html {
        font-size: 16px;
    }
}