Search Bar in Primary Menu in Genesis Version: 2.6.0

menu-search-bar-genesis-v2.6.0.css

/* Optimize Search Bar in Primary Menu */

[type=search] {
    width: auto;
}

input[type="submit"] {
    font-size: 19px;
}

.right.search, .search-bar {
    float: right;
}

.search-form input[type="submit"] {
    margin-top: 0;
}

.genesis-nav-menu .menu-item {
    padding: 7px;
}

/* Adjustment for Mobile Devices (Add this code snippet to 
the appropriate media queries on your stylesheet) */

@media only screen and (max-width: 1023px) {
.genesis-nav-menu .menu-item {
    padding: 0;
}

.right.search, .search-bar {
    float: left;
}
}

search-bar-primary-menu.php

// Add a Search Bar to PRIMARY Navigation Menu
add_filter( 'wp_nav_menu_items', 'theme_menu_extras', 10, 2 );
function theme_menu_extras( $menu, $args ) {

	if ( 'primary' !== $args->theme_location )
		return $menu;
	
	$menu  .= '<li class="search-bar">' . get_search_form( false ) . '</li>';

	return $menu;

}