main{
    position: relative;
}
.promotion{
    position: fixed;
    right: 50px;
    bottom: 75px;
    z-index: 100;
}
.promotion>div{
    position: relative;
}
.promotion>div a{
    display: block;
}
.promotion>div button{
    position: absolute;
    top: -10px;
    left: -10px;
    background: none;
    border: none;
}
.promotion>div button:hover{
    cursor: pointer;
}
@media screen and (max-width: 768px){
    .promotion{
        right: 0;
        bottom: 100px;
    }
}