double-bounce.css in Ajax loader 7

.ajax-throbber.sk-double-bounce .sk-child {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background-color: #333;
    opacity: 0.6;
    position: absolute;
    top: 0;
    left: 0;
    -webkit-animation: sk-doubleBounce 2s infinite ease-in-out;
    animation: sk-doubleBounce 2s infinite ease-in-out; }
.ajax-throbber.sk-double-bounce .sk-double-bounce2 {
    -webkit-animation-delay: -1.0s;
    animation-delay: -1.0s; }

@-webkit-keyframes sk-doubleBounce {
    0%, 100% {
        -webkit-transform: scale(0);
        transform: scale(0); }
    50% {
        -webkit-transform: scale(1);
        transform: scale(1); } }

@keyframes sk-doubleBounce {
    0%, 100% {
        -webkit-transform: scale(0);
        transform: scale(0); }
    50% {
        -webkit-transform: scale(1);
        transform: scale(1); } }