.upload-zone.dragover{border-color:#e53e3e;background:#fff5f5;transform:scale(1.02)}.file-preview.active{display:block}.loading.active{display:inline-block;width:20px;height:20px;border:2px solid #fff;border-radius:50%;border-top-color:transparent;animation:spin 1s ease-in-out infinite}.progress-bar.active{display:block}.success-message.active{display:block}