How can i make my categories to expand on hovering?

Hello Hrashit !
To make the categories to expand on hovering in the DW Focus, please do as the following: 
1. log in to Dashboard > Categories > add new (categories & subcategories )
E.g: 
       Categories
            – Subcategories1
            – Subcategories 2
2. Add new posts, select the categories & Subcategories
Notice: add the image to Feature Image.
3. After adding posts & categories, you need to add the menu.
Open Menu section, select the categories, click add to menu.
After items have been added to a menu, drag and drop to put them in the order you want. You can also click each item to reveal additional configuration options. You can also drag a menu item a little to the right to make it a submenu, to create menus with hierarchy.
You’ll see when the position of the drop target shifts over to portray the nested placement. When you have finished building your custom menu, make sure you click the Save Menu button.
See the screenshot: 
Hope this helps !