#loader {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 999; /* Sit on top */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: hidden; /* Disable scroll */
    background: rgba(255, 255, 255, 0.8); /* White background with opacity */
}
#loader .spinner {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    border: 12px solid #f3f3f3; /* Light grey */
    border-top: 12px solid #3498db; /* Blue */
    border-radius: 50%;
    width: 80px;
    height: 80px;
    animation: spin 2s linear infinite;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}