.shadow-drop-center {
    -webkit-animation: shadow-drop-center 0.5s ease-in-out infinite alternate-reverse both;
    animation: shadow-drop-center 0.5s ease-in-out infinite alternate-reverse both;
}

@-webkit-keyframes shadow-drop-center {
    0% {
        -webkit-box-shadow: 0 0 0 0 rgba(76, 161, 246);
        box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
    }

    100% {
        -webkit-box-shadow: 0 0 20px 0px rgba(162, 206, 250);
        box-shadow: 0 0 20px 0px rgba(162, 206, 250);
    }
}

@keyframes shadow-drop-center {
    0% {
        -webkit-box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
        box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
    }

    100% {
        -webkit-box-shadow: 0 0 20px 0px rgba(162, 206, 250);
        box-shadow: 0 0 20px 0px rgba(162, 206, 250);
    }
}