.nli-loader {
    display: inline-block;
    width: 30px;
    height: 30px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 10px;
}

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

.hidden {
    display: none !important;
}

.csv-error {
    color: red;
    margin-top: 10px;
    font-weight: bold;
    display: none;
}