<style>
.phone-call {
    width: 50px;
    height: 50px;
    left: 20px;
    bottom: 20px;
    background: #10b418;
    position: fixed;
    text-align: center;
    color: #ffffff;
    cursor: pointer;
    border-radius: 50%;
    z-index: 99;
  display: inline-block;
  line-height: 45px;
}

.phone-call:before {
    position: absolute;
    content: " ";
    z-index: -1;
    top: -15px;
    left: -15px;
    background-color: #10b418;
    width: 80px;
    height: 80px;
    border-radius: 100%;
    animation-fill-mode: both;
    -webkit-animation-fill-mode: both;
    opacity: 0.6;
    -webkit-animation: pulse 1s ease-out;
    animation: pulse 1.8s ease-out;
    -webkit-animation-iteration-count: infinite;
    animation-iteration-count: infinite;
}

@-webkit-keyframes pulse {
    0% {
        -webkit-transform: scale(0);
        opacity: 0;
    }
    25% {
        -webkit-transform: scale(0.3);
        opacity: 1;
    }
    50% {
        -webkit-transform: scale(0.6);
        opacity: .6;
    }
    75% {
        -webkit-transform: scale(0.9);
        opacity: .3;
    }
    100% {
        -webkit-transform: scale(1);
        opacity: 0;
    }
}

@keyframes pulse {
    0% {
        transform: scale(0);
        opacity: 0;
    }
    25% {
        transform: scale(0.3);
        opacity: 1;
    }
    50% {
        transform: scale(0.6);
        opacity: .6;
    }
    75% {
        transform: scale(0.9);
        opacity: .3;
    }
    100% {
        transform: scale(1);
        opacity: 0;
    }
}


</style>

<div class="phone-call">
    <a href="https://wa.me/8181837402"><img src="https://cdn2.iconfinder.com/data/icons/social-messaging-ui-color-shapes-2-free/128/social-whatsapp-circle-512.png" width="50" alt="Call Now" title="Call Now">
</a>
</div>