.modal-wrapper-preloader {
    position: fixed;
    top: 0px;
    left: 0px;
    z-index: 100;

    display: flex;
    align-items: center;
    justify-content: center;

    background: #FFF;

    transition: .3s;

    width: 100vw;
    height: 100vh;
}

.overflow-hidden { overflow: hidden; }

.modal-wrapper-preloader-hidden { opacity: 0; }

.preloader {
    width: 100px;
    height: 100px;

    border-radius: 50%;
    border: 3px solid transparent;
    border-top-color: #000;

    animation: preloader-spin 2s linear infinite;
}
.preloader:before {
    content: "";

    position: absolute;

    top: 5px;
    left: 5px;
    right: 5px;
    bottom: 5px;

    border-radius: 50%;
    border: 3px solid transparent;
    border-top-color: #7f8183;

    animation: preloader-spin 3s linear infinite;
}
.preloader:after {
    content: "";

    position: absolute;
    top: 15px;
    left: 15px;
    right: 15px;
    bottom: 15px;

    border-radius: 50%;
    border: 3px solid transparent;
    border-top-color: #000;

    animation: preloader-spin 1.5s linear infinite;
}

@keyframes preloader-spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (min-width: 0px) and (max-width: 600px) {
    .preloader {
        width: 70px;
        height: 70px;
    }
}