html, body { margin: 0; height: 100%; background-color: #1D1D1D; }
#app-loading {
    position: fixed; inset: 0;
    display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    background-color: #1D1D1D; color: #B2B2B2;
    font-family: sans-serif; font-size: 14px;
    z-index: 9999;
}
#app-loading .app-loading-spinner {
    width: 48px; height: 48px;
    border: 4px solid rgba(255, 255, 255, 0.15);
    border-top-color: var(--app-loading-spinner-color, #06CFFF);
    border-radius: 50%;
    animation: app-loading-spin 0.9s linear infinite;
    margin-bottom: 16px;
}
@keyframes app-loading-spin { to { transform: rotate(360deg); } }