/* OVERLAY DE FUNDO */
#loadingOverlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.45);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 99999;
    visibility: hidden;
    opacity: 0;
    transition: opacity .25s ease, visibility .25s ease;
}

#loadingOverlay.show {
    visibility: visible;
    opacity: 1;
}

.loader {
    border: 8px solid #d9d9d9;
    border-top: 8px solid #3498db;
    border-radius: 50%;
    width: 70px;
    height: 70px;
    animation: spin 1s linear infinite;
}

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