Simple Responsive Menu is a free extension, but very useful as it allows you to set the site a separate module, which will change automatically. For example, you will not see any differences on the page, until you change the scale or use your mobile phone or tablet.
Simple Responsive Menu

The essence of this module is obvious – to place the menu items on the screen, no matter what version you do not use – mobile or desktop. If you go with a desktop computer, you will see the following picture:
The vertical menu allows you to change the drop-down list to change the width of the page. In module settings you can set the width size by which you want to change the type and appearance of the menus. Now you do not need to ensure that all menu items should fit both the normal and the mobile version of your project.
Automatic change of the menu to edit the width of the page.
Custom menu items.
Simple integration into the available settings and parameters.