Made by Rich Tabor using the following materials: Columns block, Group block.
<!-- wp:columns -->
<div class="wp-block-columns"><!-- wp:column -->
<div class="wp-block-column"><!-- wp:group {"style":{"spacing":{"padding":{"top":"50%","right":"0%","bottom":"0%","left":"0%"}},"border":{"radius":{"bottomLeft":"100vw","bottomRight":"100vw"}}},"gradient":"diagonal-primary-to-foreground","layout":{"inherit":false}} -->
<div class="wp-block-group has-diagonal-primary-to-foreground-gradient-background has-background" style="border-bottom-left-radius:100vw;border-bottom-right-radius:100vw;padding-top:50%;padding-right:0%;padding-bottom:0%;padding-left:0%"></div>
<!-- /wp:group --></div>
<!-- /wp:column --></div>
<!-- /wp:columns -->
<!-- wp:columns -->
<div class="wp-block-columns"><!-- wp:column -->
<div class="wp-block-column"><!-- wp:group {"style":{"spacing":{"padding":{"top":"50%","right":"0%","bottom":"0%","left":"0%"}},"border":{"radius":{"topLeft":"100vw","topRight":"100vw","bottomLeft":"0vw","bottomRight":"0vw"}}},"gradient":"vertical-tertiary-to-background","layout":{"inherit":false}} -->
<div class="wp-block-group has-vertical-tertiary-to-background-gradient-background has-background" style="border-top-left-radius:100vw;border-top-right-radius:100vw;border-bottom-left-radius:0vw;border-bottom-right-radius:0vw;padding-top:50%;padding-right:0%;padding-bottom:0%;padding-left:0%"></div>
<!-- /wp:group --></div>
<!-- /wp:column --></div>
<!-- /wp:columns -->