Off-canvas
CSS ONLY
The Off-canvas is a navigation layout that the sidebar can slide in and out of the viewport. It is built in pure CSS.
              By default, the off-canvas menu is collapsed whenever the window width is.
              But you can add the off-canvas-sidebar-show class to the off-canvas to make the sidebar expanded when the window width is larger than or equal to 960px.
            
You can open the sidebar by adding the class active to off-canvas-sidebar.
              And remove the active to close it.
            
<div class="off-canvas">
  <!-- off-screen toggle button -->
  <a class="off-canvas-toggle btn btn-primary btn-action" href="#sidebar-id">
    <i class="icon icon-menu"></i>
  </a>
  <div id="sidebar-id" class="off-canvas-sidebar">
    <!-- off-screen sidebar -->
  </div>
  <a class="off-canvas-overlay" href="#close"></a>
  <div class="off-canvas-content">
    <!-- off-screen content -->
  </div>
</div>