.down{
    position: absolute;
    top: 51%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    border-radius: 50%;
    border: 2px solid #00567D;
    background: #04a9f5;
    box-shadow: 0 0 5px #fff, 0 5px 25px rgba(0, 0, 0, .8);
    margin-top: -10%;

}

.down .fa {
    position: absolute ;
    font-size: 50px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
    transform: translate(-50%, -50%);
    animation: animate  1.5s linear infinite;
    text-shadow: 0px 2px 5px rgba(0, 0, 0, .2);
    overflow: hidden;   
}
@keyframes animate {
    0%{
        top: -10%;
    }
    40%{
        top: 60%;
    }
    60%{
        top: 30%;
    }
    80%{
        top: 60%;
    }
    100%{
        top: 110%;
    }
    
}
@media(max-width: 991px){
    .down{
        position: none;
        margin-top: -20%;
    }
    .down .fa{
    }
    .abd{
    margin-top: 20%;
}
}