Menu elements shifting when made bold on hover

Question

I'm creating a website in Wordpress using page builder Elementor.

The menu should have a font weight of 900 on hover.

Problem is that the whole menu is shifting the size on hovering then. I saw this solution on another thread, but I couldn't make it work for my site. Does anyone have a clue how to solve this in my setting?

selector a:hover{
    color: #737373 !important;
    font-weight:900 !important;
}