@keyframes pulse {
0%{ box-shadow: 0 0 0 0px rgba(255,255,255, 0.8);}
100%{ box-shadow: 0 0 0 25px rgba(255,255,255, 0);}
}
.pulse:before {
content: '';
display: block !important;
position: absolute;top: 0;left: 0;
width: 100%;height: 100%;
border-radius: 50%;
animation: pulse 2s infinite;
}

.pulse:nth-child(2n):before {
animation-duration: 2.2s;
animation-delay: 0.3s
}

.pulse:nth-child(3n):before {
animation-duration: 1.8s;
animation-delay: 0.6s
}

.pulse.active:before{
animation: none;
}