Gutenberg

Reusable Blocks in Admin Menu

function be_reusable_blocks_admin_menu() {
    add_menu_page( 'Reusable Blocks', 'Reusable Blocks', 'edit_posts', 'edit.php?post_type=wp_block', '', 'dashicons-editor-table', 22 );
}
add_action( 'admin_menu', 'be_reusable_blocks_admin_menu' );

Color Palette for Gutenberg

add_action( 'after_setup_theme', function() {
    add_theme_support( 'editor-color-palette', array(
        array(
            'name'  => __( 'Blue' ),
            'slug'  => 'blue',
            'color' => '#59BACC',
        ),
        array(
            'name'  => __( 'Green' ),
            'slug'  => 'green',
            'color' => '#58AD69',
        ),
        array(
            'name'  => __( 'Orange' ),
            'slug'  => 'orange',
            'color' => '#FFBC49',
        ),
        array(
            'name'  => __( 'Red' ),
            'slug'  => 'red',
            'color' => '#E2574C',
        ),
    ) );
} );