tsquez

.in-sub-panel #customize-theme-controls .customize-pane-child.current-panel-parent,
#customize-theme-controls .customize-pane-child.current-section-parent {
  -webkit-transform: translateX(-100%);
  -ms-transform: translateX(-100%);
  transform: translateX(-100%);
}

tsquez

<aside class="left-off-canvas-menu">
<?php wp_nav_menu(
	array(
		'theme_location' => 'the menu you want to use',
		'container' => false,
		'menu_id' => '',
		'menu_class' => 'off-canvas-list',
		'walker' => new Off_Canvas_Walker()
	)
);