Setting up sub-menu items for a main menu item is an easy routine through drag and drop in menus section of WordPress Dashboard. In majority of WordPress Themes, when you hover over sub-menu items the parent main menu item is no longer highlighted. Do you want to keep the main parent menu item highlighted while hovering over its sub-menu items?
Visual Demo: Highlight Menu item while sub menu hover
On left, while hovering over sub-menu items like: SEO Optimization, Web Design, Online Development – the main parent menu “Services” is not highlighted. While on right side, then main menu “Services” is highlighted while hovering over sub-menu items.
The second (right side) setup look much better and it is very easy to achieve. Just one line of css code in your style.css file.
Required CSS code for this modification
Just add following code to your style.css file. Make sure you change background color and text color according to existing settings of the primary menu. Also, replace the class name being used for menu in your WordPress Theme. It could be .nav in place of .nav-primary class.
More neater way to implement this is by adding it to existing .nav-primary a:hover section as seen in screenshot below: