mixitup plugin - i cant doing work

Question

The plugin seems to work but when i click on the filter, fade the correct items but then are shown all of them again.

This is the code i have:

echo '<div id="inner-archive">'; ?>

        <div id="portfolio-wrapper">
        <ul id="portfolio-list">
        <?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?> 
        <?php $tags = get_the_tags();
            foreach($tags as $tag){
                $tag = str_replace(' ', '-', $tag->name);
            }
            echo '<li class="mix ' . $tag . '" data-cat="' . $tag . '">'; ?>
            <a href="<?php the_permalink() ?>">
                <div class="archives-post-thumbnail">
                    <?php if ( has_post_thumbnail() ) {
                    the_post_thumbnail('fab-450');
                    } ?>
                </div>
            </a>
            </li>
        <?php endwhile; ?> 
        <?php endif;?>
        </ul>
        </div>


        <?php  fab_pagination();
        echo '</div></section><div id="fix-sidebar" class="recursos-sidebar">';
        $tags = get_tags();
        if ($tags) {
            echo '<ul id="portafolio-filter">';
            foreach ( $tags as $tag ) {
                $tag = str_replace(' ', '-', $tag->name);?>
                <li class="filter" data-filter="<?php echo $tag ?>"><?php echo $tag ?></li>
        <?php }
        echo '</ul>';
    }
    echo '</div></div>';

And the jQuery:

jQuery(document).ready(function(){
    jQuery('#portfolio-list').mixitup(); 
});

Thanks! I hope someone can help me

Answer 1

Sorry, i found the error.

I forgot to put the css code.

#Grid .mix{
    opacity: 0;
    display: none;
}