resolved an issue by making the vertical separator borders, between the sidebars and the content, to touch the bottom of the primary navigation (that is, removed the spacing between the vertical borders and the primary navigation).
But, it also removed the spacing between the content headings and the primary navigation.
Please, how can the spacing between the content headings and the primary navigation be restored back?
Sounds good – try using Firefox and the “Firebug” extension. It allows you to right click an element and add CSS to it – then once you get the right CSS, you can save it and add it to your child theme 🙂
You can download Firefox here. As Tom mentioned, when you right-click on a page and select “Inspect element” it will open a Firebug window that allows you to add css in “real time” and see the effects on the page. IE and Chrome have the same functionality.