.loader-wrapper
    {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        z-index: 1000;
    }

.loader {
    display: block;
    position: relative;
    left: 50%;
    top: 50%;
    width: 128px;
    height: 128px;
    margin: -64px 0 0 -64px;
    border-radius: 50%;
    border: 3px solid transparent;
    border-top-color: #00bfa5;
    -webkit-animation: spin 2s linear infinite; /* Chrome, Opera 15+, Safari 5+ */
    animation: spin 2s linear infinite; /* Chrome, Firefox 16+, IE 10+, Opera */
}

    .loader:before {
        content: "";
        position: absolute;
        top: 5px;
        left: 5px;
        right: 5px;
        bottom: 5px;
        border-radius: 50%;
        border: 3px solid transparent;
        border-top-color: #3498db;
        -webkit-animation: spin 3s linear infinite; /* Chrome, Opera 15+, Safari 5+ */
        animation: spin 3s linear infinite; /* Chrome, Firefox 16+, IE 10+, Opera */
    }

    .loader:after {
        content: "";
        position: absolute;
        top: 15px;
        left: 15px;
        right: 15px;
        bottom: 15px;
        border-radius: 50%;
        border: 3px solid transparent;
        border-top-color: #455a64;
        -webkit-animation: spin 1.5s linear infinite; /* Chrome, Opera 15+, Safari 5+ */
        animation: spin 1.5s linear infinite; /* Chrome, Firefox 16+, IE 10+, Opera */
    }

@-webkit-keyframes spin {
    0% {
        -webkit-transform: rotate(0deg); /* Chrome, Opera 15+, Safari 3.1+ */
        -ms-transform: rotate(0deg); /* IE 9 */
        transform: rotate(0deg); /* Firefox 16+, IE 10+, Opera */
    }

    100% {
        -webkit-transform: rotate(360deg); /* Chrome, Opera 15+, Safari 3.1+ */
        -ms-transform: rotate(360deg); /* IE 9 */
        transform: rotate(360deg); /* Firefox 16+, IE 10+, Opera */
    }
}

@keyframes spin {
    0% {
        -webkit-transform: rotate(0deg); /* Chrome, Opera 15+, Safari 3.1+ */
        -ms-transform: rotate(0deg); /* IE 9 */
        transform: rotate(0deg); /* Firefox 16+, IE 10+, Opera */
    }

    100% {
        -webkit-transform: rotate(360deg); /* Chrome, Opera 15+, Safari 3.1+ */
        -ms-transform: rotate(360deg); /* IE 9 */
        transform: rotate(360deg); /* Firefox 16+, IE 10+, Opera */
    }
}