重なるボックス（縦）

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<div class="wp-block-group has-no-st-margin-bottom is-style-st-wide-background has-white-color has-very-dark-gray-background-color has-text-color has-background" style="padding-bottom:var(--wp--preset--spacing--70)"><!-- wp:paragraph -->
<p>これはダミーのテキストです</p>
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<!-- /wp:group -->

<!-- wp:group {"backgroundColor":"white","className":"has-st-border has-st-solid-border has-st-medium-border-width mt-30 st-box-shadow","layout":{"type":"constrained"},"stBorderStyle":"solid"} -->
<div class="wp-block-group has-st-border has-st-solid-border has-st-medium-border-width mt-30 st-box-shadow has-white-background-color has-background"><!-- wp:paragraph {"className":""} -->
<p>これはダミーのテキストです</p>
<!-- /wp:paragraph --></div>
<!-- /wp:group -->