You can see the Top Bar at the top of this page. It is currently active. Go ahead and close it.
Some themes have fixed menus and in this case the Top Bar will work better if positioned at the bottom of the screen.
We cannot predict if the plugin will play nicely with your theme, we recommend downloading and trying our Free version before buying the plugin.
In case the Top Bar covers your menu (or the other way around), our developers can try to solve the issue for you, just let us know.