Display Genesis Featured Posts In Columns https://wpsites.net/web-design/display-genesis-featured-posts-in-horizontal-grid/

functions.php

genesis_register_sidebar( array(
    'id' => 'home-top',
    'name' => __( 'Home Top', 'genesis' ),
) );

add_action( 'genesis_before_content_sidebar_wrap', 'home_page_widget' );
function home_page_widget() {

    if ( is_front_page() ) {
    
    genesis_widget_area( 'home-top', array(
        'before' => '<div class="home-top widget-area">',
        'after'  => '</div>',
    ) );
    }
}

add_image_size( 'vertical-thumbnail',   680, 900, true );

style.css

.home-top .entry .entry-title {
	font-size: 16px;
	text-align: center;
}

.home-top .entry {
    display: inline-block;
    padding: 1%;
    width: 33.33333333333%;
}

@media only screen and (max-width: 860px) {

    .home-top .entry {
        display: inline-block;
        width: 100%;
}
	
// Another method
	
.home-top .entry {
    width: 31.6239%;
    float: left;
    margin-left: 2.5641%;
 }
 
.home-top .entry:nth-of-type(3n+1){
    margin-left: 0;
}

.home-top .entry .entry-title {
    font-size: 16px;
    text-align: center;
}

@media only screen and (max-width: 860px) {

    .home-top .entry {
        width: 100%;
        float: none;
        margin: auto;
    }
    
    .home-top {
        margin-bottom: 40px;
    }
    
}