diff --git a/packages/block-library/src/post-template/style.scss b/packages/block-library/src/post-template/style.scss
index e6896f2db024a8..f222c8496118a3 100644
--- a/packages/block-library/src/post-template/style.scss
+++ b/packages/block-library/src/post-template/style.scss
@@ -31,7 +31,7 @@
 
 @media ( max-width: $break-small ) {
 	// Temporary specificity bump until "wp-container" layout specificity is revisited.
-	.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid {
+	.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid.wp-block-post-template-is-layout-grid, .is-layout-grid.wp-block-group-is-layout-grid {
 		grid-template-columns: 1fr;
 	}
 }