Pattern visibility on click? | WordPress.org

I’m pretty green when it comes to WordPress development and creating a block theme, so perhaps this has a really simple answer I’m overlooking, but I’m not enthused with the styling on the Navigation block’s hamburger menu, so I created a pattern that has everything laid out the way I’d like it. I’m just not sure how to set it to reveal on a button click. I can add it to the header template part, and even set the class to “hidden-by-default” but I’m not sure how I would get the hamburger menu button to reveal that div on click.

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