.loading-spinner {
    border: 2px solid #f3f3f3;
    border-top: 2px solid #3498db;
    border-radius: 50%;
    width: 16px;
    height: 16px;
    animation: spin 1s linear infinite;
    display: inline-block;
    vertical-align: middle;
    margin-left: 8px;
}

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

    100% {
        transform: rotate(360deg);
    }
}

.btn-loading {
    pointer-events: none;
    opacity: 0.6;
}