.btn1
{
    top: 82.5%;
  
}

.btn1 img{
    width: 60%;
    max-width: 599px;
    animation: pulse 0.8s infinite;
    animation-timing-function: linear;  
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1);}
    100% { transform: scale(1); }
} 

 /* Large devices (desktops, 992px and up) */
@media (min-width: 992px) { 
    #bg{
        height: 100vh;
    }

 }