#loader {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.8);
    z-index: 9999;
}
.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #ddd;
    border-top-color: #333;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}