.navbar { display: none; }

Editing The Mobile Menu

The below instructions are available for installations with the "Menu Pro" Live Composer extension. This add-on is delivered in theme versions above to 1.9.

1
Go to WP Admin > Appearance > Headers/Footers and select the header you are using. In the case you are using the demo content, open in Live Composer the "Header - default design".
2
Mouse over the menu module until the module settings panel is displayed. Click on the cog icon.
3
On the "Mobile Navigation" feature select your menu which will be displayed on the mobile off-canvas panel.
4
On the "Style" tab you have multiple options for customization. 

Note:

If you are using theme version below to 1.8.7, or still use the Mega Main Menu plugins, to change mobile menu please go to  WP Admin > Appearance > Widgets > Mobile: Off-canvas Panel. See this screenshot of the widget area where you need to drop a "Custom menu" widget.