#progress-layer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 999999;
    pointer-events: none;

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

    background: #000;
    animation-duration: 600ms;
    animation-timing-function: ease-in-out;
}

@keyframes fade-out {
    from { opacity: 0.85 }
      to { opacity: 0 }
}

@keyframes fade-in {
    from { opacity: 0 }
      to { opacity: 0.85 }
}

#progress-loader {
    animation-duration: 600ms;
    animation-timing-function: ease-in-out;
}

#progress-layer.fade-out {
    opacity: 0;
    animation-name: fade-out;
}

#progress-layer.fade-in {
    opacity: 0.85;
    animation-name: fade-in;
}

#progress-loader {
    border: 10px solid #444;
    border-top: 10px solid #222;
    border-radius: 50%;
    width: 100px;
    height: 100px;
    animation: spin .9s linear infinite;
}

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