Lost styles when landing an element on the engine?

Question

MODX

I comprehend MODX Revolution, the question is quite childish, I guess.
The document has a menu:

<ul class="sidebar__list">
    <li class="sidebar__item"><a href="index.php">Main page</a></li>
    <li class="sidebar__item"><a href="gallery.php">Gallery</a></li>
    <li class="sidebar__item"><a href="contacts.php">Contacts</a></li>
</ul>

In the process of landing on the engine, this fragment is replaced by the text of the chunk: Everything seems to be very good, but on the site page, the items of this menu appear completely without styles, since the classes are obviously lost. The question is what am I doing wrong? Thank you very much in advance.

Answer 1

The question is what am I doing wrong?

Do not read the instructions for the component .