/* Simple spinner overlay for loading indication */
.spinner-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(255,255,255,0.7);
    z-index: 9999;
    display: none;
}
.spinner-overlay.show {
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
}
.spinner {
    border: 8px solid #f3f3f3;
    border-top: 8px solid #007bff;
    border-radius: 50%;
    width: 60px;
    height: 60px;
    animation: spin 1s linear infinite;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}