themes-wordpress/masu/templates/index.html

<!-- wp:template-part {"slug":"header","tagName":"header"} /-->

<!-- wp:group {"tagName":"main","style":{"spacing":{"margin":{"top":"0","bottom":"0"}}},"layout":{"inherit":true,"type":"constrained"}} -->
<main class="wp-block-group" style="margin-top:0;margin-bottom:0">
	<!-- wp:pattern {"slug":"masu/grid-of-posts"} /-->
</main>
<!-- /wp:group -->

<!-- wp:template-part {"slug":"footer","tagName":"footer","className":"site-footer-container"} /-->