.loader-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    visibility: hidden;
    opacity: 1;
    transition: visibility 0s, opacity 0.3s ease-in-out;
}

.loader-overlay.visible {
    visibility: visible;
    opacity: 0.7;
}

.loader-overlay::after {
    content: '';
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3498db;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
}

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