html, body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}

#loader-box {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.loader, .loader:before, .loader:after {
    border-radius: 50%;
    width: 2.5em;
    height: 2.5em;
    animation-fill-mode: both;
    animation: bblFadInOut 1.8s infinite ease-in-out;
}

.loader {
    color: #000000;
    font-size: 7px;
    position: relative;
    text-indent: -9999em;
    transform: translateZ(0);
    animation-delay: -0.16s;
}

.loader:before,
.loader:after {
    content: '';
    position: absolute;
    top: 0;
}

.loader:before {
    left: -3.5em;
    animation-delay: -0.32s;
}

.loader:after {
    left: 3.5em;
}

@keyframes bblFadInOut {
    0%, 80%, 100% {
        box-shadow: 0 2.5em 0 -1.3em
    }
    40% {
        box-shadow: 0 2.5em 0 0
    }
}