#loadingMessage:not([hidden]) p::before,
.pdf-viewer__message.is-loading::before {
    content: '';
    display: block;
    box-sizing: border-box;
    width: 20px;
    height: 20px;
    margin: 0 auto 10px;
    border: 2px solid #f1dcc8;
    border-top-color: #d78d53;
    border-radius: 50%;
    animation: archive-loading-spin .85s linear infinite;
}
#loadingMessage[hidden] {
    display: none;
}
@keyframes archive-loading-spin {
    to { transform: rotate(360deg); }
}
@media (prefers-reduced-motion: reduce) {
    #loadingMessage:not([hidden]) p::before,
    .pdf-viewer__message.is-loading::before {
        animation: none;
    }
}