Styling Select box with jQuery in WordPress

Just trying to style a select box on a WordPress project with jQuery using this plugin.

http://plugins.jquery.com/project/stylish-select-box/

jQuery(document).ready(function(){
    // select box styles
    jQuery('#genre-dropdown').sSelect(); 
});

When I call it on the select box it displays two copies of .newListSelected (the stylable list) instead of one. Below is the code used to produce the select box.

<?php 

$args = array(
    'taxonomy' => 'genre',
    'id'       => 'genre-dropdown',
);

wp_dropdown_categories( $args );

?>

I've tried with 开发者_JAVA技巧no argument for the custom taxonomy and on a totally different page with the same results.

---

The original URL is dead, and I tested with SelectBoxIt. The following example creates an admin menu that displays a styled categories dropdown. The key detail is to load the jQuery plugin adding the bundled WordPress scripts as dependencies, see Don't dequeue WordPress jQuery.

File wp-content/plugins/my-plugin/styled-dropdown.php:

<?php
/* Plugin Name: Styled Dropdown */

add_action( 'admin_menu', 'add_menu_so_3216591' );

function add_menu_so_3216591() 
{
    add_menu_page(
        'SI', 
        '<span style="color:#e57300;">SelectIt</span>', 
        'edit_pages', 
        'so-3216591', 
        'menu_page_so_3216591',
        '', // icon default for empty
        1  // create before Dashboard menu item
    );
}

function menu_page_so_3216591() 
{
    wp_enqueue_style( 
        'select-it', 
        'http://cdnjs.cloudflare.com/ajax/libs/jquery.selectboxit/3.7.0/jquery.selectBoxIt.css' 
    );
    wp_enqueue_style( 
        'jquery-ui', 
        'http://ajax.googleapis.com/ajax/libs/jqueryui/1.9.2/themes/base/jquery-ui.css' 
    );
    # Will be used as dependency bellow
    wp_register_script(
        'select-it', 
        'http://cdnjs.cloudflare.com/ajax/libs/jquery.selectboxit/3.7.0/jquery.selectBoxIt.min.js'
    );
    # Main script and dependencies 
    wp_enqueue_script(
        'do-it', 
        plugins_url( '/js/', __FILE__ ) . 'do-it.js',
        array( 'jquery', 'jquery-ui-widget', 'select-it' ) // Dependencies: using bundled WordPress scripts (highly recommended)
    );
    ?>
    <div id="icon-post" class="icon32"></div>
    <h2>Testing Select Box It</h2>
    <p><?php wp_dropdown_categories( array( 'id'=>'select-it-dd' ) ); ?></p>
    <?php
}

And the file wp-content/plugins/my-plugin/js/do-it.js:

jQuery(document).ready(function($) 
{   
    $("#select-it-dd").selectBoxIt(
    {
        theme: "jqueryui"
    });
});