How to style shortcode | WordPress.org

Hi, opening another thread, I have added a “Block” and managed to add in the shortcode:

<h6 class=”widget-title”><strong>Popular Posts</strong></h6>[wpp range=’last30days’ stats_views=0]

But I was not able to get it to look the same as before. I have tried to edit the settings.php at:

'markup' => [
                'custom_html' => true,
                'title-start' => '<h2>',
                'title-end' => '</h2>',
                'wpp-start' => '<class="wpp-list">',
                'wpp-end' => '</class>',
                'post-html' => '{title}<br>'
            ]

However, it did not work. May I know how can I style it to look similar to before? Thank you.

Ideally, I do not want to touch the settings.php code as it may mess up other things.

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