Only add the container class if we are in the new enable_side_menu mode since it could casue issues with backwards compatiblity and css

dalston/header.php

@@ -61,14 +61,15 @@ $header_classes .= $has_primary_nav ? ' has-menu' : '';
 						<span class="hide-visually collapsed-text"><?php _e( 'collapsed', 'varia' ); ?></span>
 					</label>
 					<?php
-					wp_nav_menu(
-						array(
-							'container_class' => 'main-menu-container',
-							'theme_location'  => 'menu-1',
-							'menu_class'      => 'main-menu',
-							'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
-						)
+					 $main_nav_args = array(
+						'theme_location'  => 'menu-1',
+						'menu_class'      => 'main-menu',
+						'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
 					);
+					if ( get_theme_mod( 'enable_side_menu' ) === 1 ) {
+						$main_nav_args[ 'container_class' ] = 'main-menu-container';
+					}
+					wp_nav_menu( $main_nav_args );
 					?>
 				</nav><!-- #site-navigation -->
 			<?php endif; ?>

morden/header.php

@@ -62,14 +62,15 @@ if ( function_exists( 'wp_body_open' ) ) {
 						</label>
 
 						<?php
-						wp_nav_menu(
-							array(
-								'container_class' => 'main-menu-container',
-								'theme_location'  => 'menu-1',
-								'menu_class'      => 'main-menu',
-								'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
-							)
+						$main_nav_args = array(
+							'theme_location'  => 'menu-1',
+							'menu_class'      => 'main-menu',
+							'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
 						);
+						if ( get_theme_mod( 'enable_side_menu' ) === 1 ) {
+							$main_nav_args[ 'container_class' ] = 'main-menu-container';
+						}
+						wp_nav_menu( $main_nav_args );
 						?>
 					</nav><!-- #site-navigation -->
 				<?php endif; ?>

varia/header.php

@@ -61,14 +61,15 @@ if ( function_exists( 'wp_body_open' ) ) {
 					</label>
 
 					<?php
-					wp_nav_menu(
-						array(
-							'container_class' => 'main-menu-container',
-							'theme_location'  => 'menu-1',
-							'menu_class'      => 'main-menu',
-							'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
-						)
+					$main_nav_args = array(
+						'theme_location'  => 'menu-1',
+						'menu_class'      => 'main-menu',
+						'items_wrap'      => '<ul id="%1$s" class="%2$s" aria-label="submenu">%3$s</ul>',
 					);
+					if ( get_theme_mod( 'enable_side_menu' ) === 1 ) {
+						$main_nav_args['container_class'] = 'main-menu-container';
+					}
+					wp_nav_menu( $main_nav_args );
 					?>
 				</nav><!-- #site-navigation -->
 			<?php endif; ?>