.pages-banner-box,
.pages-video-box{
    width: 100%;
    display: block;
    position: relative;
    overflow: hidden;
}
.pages-banner-bc{
    width: 100%;
    height: 400px;
    display: block;
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    position: relative;
}
.pages-video{
    width: 100%;
    height: calc((400 / 1920) * 100vw);
    display: block;
}
.pages-banner-img-mask{
    width: 100%;
    height: 100%;
    display: block;
    background-color: #000;
    position: absolute;
    top: 0;
    left: 0;
}
.pages-banner-circle-box{
    width: calc(100% + 60px);
    height: 40px;
    border-radius: 50% 50% 0 0 / 100% 100% 0 0;
    position: absolute;
    bottom: -8px;
    left: -30px;
    background-color: #fff;
}

#about .pages-banner-box{
    height: 300px;
}
#about .pages-banner-bc{
    position: absolute;
    top: 0;
    left: 0;
    overflow: hidden;
}
#about .pages-banner-circle-box,
#school .pages-banner-circle-box{
    background-color: #f5f5f5;
}





@media only screen and (max-width: 1000px){
    #about .pages-banner-box{
        height: 200px;
    }
    #about .pages-banner-bc{
        height: 300px;
    }
    .pages-banner-bc{
        height: 300px;
    }
}
@media only screen and (max-width: 750px){
    .pages-banner-circle-box{
       display: none;
    }
}
@media only screen and (max-width: 550px){
    #about .pages-banner-box{
        height: 150px;
    }
    #about .pages-banner-bc{
        height: 100%;
    }
    .pages-banner-bc,
    .pages-video{
        height: 150px;
    }
}
@media only screen and (max-width: 400px){
    #about .pages-banner-box{
        height: 100px;
    }
    .pages-banner-bc{
        height: 100px;
    }
}