Hard time editing with a child theme? Secondary nav & random 404 errors.

This theme (Pagelines DMS, I believe?) is killing me – I’m having a hard time locating the existing code for (what they call) the secondary nav bar, at the very top of this website. I’m specifically looking for where to edit the font size and color of the top nav links, if there is any existing code for that.

In addition, my created test posts are causing 404 errors and I’m not sure why. ??

Thanks in advance for any suggestions!