Never mind–I figured out how to do it with grid. I had to add a class to the shortcode, then used this css:
<div class="wpsp-align-posts">[wp_show_posts id="2733"]</div>
/* Arrange show-posts entries */
.wpsp-align-posts .wp-show-posts-inner {
display: grid;
grid-template-columns: 1fr 2fr;
grid-template-rows: auto auto auto auto;
}
.wpsp-align-posts .wp-show-posts-inner header {
grid-column: 2 / 3;
grid-row: 1 / 2;
margin-bottom: 5px;
}
.wpsp-align-posts .wp-show-posts-inner .wp-show-posts-image {
grid-column: 1 / 2;
grid-row: 1 / 4;
}
.wpsp-align-posts .wp-show-posts-inner .wp-show-posts-entry-summary {
grid-column: 2 / 3;
grid-row: 2 / 3;
margin-bottom: 5px;
}
.wpsp-align-posts .wp-show-posts-inner .wpsp-read-more {
grid-column: 2 / 3;
grid-row: 3 / 4;
}