.promotion_main {
    width: 100%;
}
.promotion_top {
    display: flex;
    justify-content: center;
}
.promotion_top > div > img {
    width: 100%;
}
.promotion_btm {
    display: flex;
    justify-content: center;
}
.promotion_btm > div {
    display: flex;
    flex-direction: column;
    justify-content: center;
}