woocommerce/plugins/woocommerce-blocks/assets/js/base/components/loading-mask/style.scss

.wc-block-components-loading-mask {
	position: relative;
	min-height: 18px + $gap;
	pointer-events: none;

	.components-spinner {
		position: absolute;
		margin: 0;
		top: 50%;
		left: 50%;
		transform: translate(-50%, -50%);
	}

	.wc-block-components-loading-mask__children {
		opacity: 0.25;
	}
}