.loader {
    border: 4px solid #f3f3f3;
    border-radius: 50%;
    border-top: 4px solid #3498db;
    width: 30px;
    height: 30px;
    -webkit-animation: spin 2s linear infinite;
    animation: spin 2s linear infinite;
    position: fixed;
    z-index: 99999;
    overflow: show;
    margin: auto;
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
}

@-webkit-keyframes spin {
    0% {
        -webkit-transform: rotate(0deg);
    }

    100% {
        -webkit-transform: rotate(360deg);
    }
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}