.loading-spinner {
    border: 4px solid #f3f3f3; 
    border-top: 4px solid #2563eb;
    border-radius: 50%; 
    width: 36px; 
    height: 36px; 
    animation: spin 1s linear infinite;
}

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

.checkerboard { 
    background-image: conic-gradient(#eee 90deg, #fff 90deg 180deg, #eee 180deg 270deg, #fff 270deg); 
    background-size: 20px 20px; 
}