dw-focus dw mega menu error in mobile

Yes, I have checked on our demo and it’s not a bug come from the theme. Currently, the DW Focus does not support to display the subcategories on the mobile while you are using the Mega Menu plugin.
About the dropdown categories on mobile, you can try the following code:

@media (max-width: 997px) {

.nav li:hover .dw-sub-menu {
 display: block;

}

.dw-sub-menu .dw_focus_widget_news_grid .post .entry-meta, .dw-sub-menu .widget_news-grid .post .entry-meta {

 display: none;

}

.nav li:hover .dw-mega-menu {

 display: block;

}

.dw-sub-menu {

 position: relative;

}

.dw-sub-menu .entry-thumbnail {

 display: none;

}

.dw-sub-menu .dw_focus_widget_news_grid .post .entry-title, .dw-sub-menu .widget_news-grid .post .entry-title {

 display:none;

}

.main-navigation .dw-mega-menu .dw-mega-menu-tabs .dw-mega-menu-tab-content {

 display: none;

}

.dw-mega-menu-tabs .dw-mega-menu-tab > a {

 width: 100%;

}

}

Hope this helps !