Page displayed => menu item to appear in bold. How to do it?

Using Pinnacle free V1.2.8 with child theme
Today, as in your demo, when someone is viewing a sub-menu page like “Single Staff”, the main menu item “Features” is not differentiated from the other main menu items; the corresponding sub-menu item “Single Staff” appears in orange when we mouse over the corresponding main menu item, here “Features”.

How can we also make the main menu item in the primary navigation to appear in bold when selected as well as when one of its sub-menu item is selected? In the case outlined above it would be the item “Features” that would appear in bold. This way, even if we do not put a title on a given page, our visitor will know from which menu item he is viewing a page.

Same request for widgets Custom Menu and Pages placed in Custom sidebars. When a visitor would be on a certain page, the corresponding menu or page title on the sidebar would be in bold.

Thanks!