@media screen and (min-width:768px) {
    .majorBox {
        display: flex;
    }

    .majorBox .img{
        width: 600px;
        height: 380px;
    }

    .majorBox .intro{
        flex: 1;
        padding-left: 30px;
    }
}

@media screen and (max-width:768px) {
    .majorBox {
        display: block;
    }
    .majorBox .img{
        width: 100%;
    }

    .majorBox .intro{
        margin-top: 30px;
    }
}

.majorBox .intro .introTitle{
    font-size: 18px;
}

.majorBox .intro .introContent{
    font-size: 16px;
    line-height: 2;
}