On the official Bootstrap website at http://v4-alpha.getbootstrap.com/examples/, you can find an off-canvas example. The example will show you how to build a toggle able off-canvas navigation menu for use with Bootstrap. You can use an off-canvas side bar in your theme too. On the smaller viewports, a page with the off-canvas menu will look like that shown in the following screenshot:
When you click the Toggle nav button in the preceding page, the page content slides to the left and the side bar becomes visible.
The off-canvas menu use the template called
template-offcanvas.php in the
theme directory/ It should contain the ...