The CSS code you provided is complete and well-structured for the campaign image block. The suggested edit you mentioned is a WordPress function for enqueueing the CSS file, which would typically go in a PHP file (like `functions.php` or a block registration file), not in the CSS file itself.

Here's how you would implement both parts:

**1. The CSS file (`assets/css/blocks/campaign-image-block.css`):**
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}