#loading {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;

    background: rgba(0, 0, 0, 0.4);
    z-index: 9999;

    display: flex;
    justify-content: center;
    align-items: center;
}

.loading-content {
    background: #fff;
    padding: 20px 30px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 0 15px rgba(0,0,0,0.2);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #ccc;
    border-top: 4px solid #333;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 10px auto;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}