How to split menu into 2 columns?

Question

Layout

How to split the menu? maybe make a little more cell, make a couple of columns?
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Answer 1

https://css-tricks.com/almanac/properties/c/columns/

Answer 2

If done through the WordPress menu mechanism, then make Genres and Platforms sub-items of the Game (arbitrary link without the link itself, put # there). You can assign arbitrary classes to them - it will be easier to style (everything in the UI menu items). And add the third level of the menu to them. Well, then two separate LIs with their classes to put in columns is a matter of technique. Inline-block, float, columns, flexbox - whatever you like.

Answer 3

Do you mean it?
I implemented it in such a way that the menu item does not open a list, but a block with the required number of lists (columns). Of the minuses - it did not work out to make it with a stretching width, I had to make it fixed. I don’t pretend to be correct, I myself am a beginner layout designer. (Not familiar with wp)
The html code itself.

<li><a>Игры</a>
              <!-- Выпадающее меню -->
           <div class="sub-menu sub-menu_games">
              <span>Жанры</span>
              <span>Платформы</span>
              <ul>
                <li><a href="#">Action</a></li>
                <li><a href="#">Adventure</a></li>
                <li><a href="#">Arcade</a></li>
                <li><a href="#">Board Game</a></li>
                ...
              </ul>
              <ul>
                <li><a href="#">PC</a></li>
                <li><a href="#">PlayStation 4</a></li>
                <li><a href="#">PlayStation 3</a></li>
                <li><a href="#">Xbox One</a></li>
                ...
              </ul>
            </div>
</li>