how to change font colours for a specific section

Hello there, I am using a template and tried to change some font colours in some places, the navigation part was easy as it’s built in with the Theme options. Yet when I tried to edit some other sections, it works when I try with ctrl+shift+i, but at the back end/css, I can’t find this solution.
Can anyone please gimme a hang on this?
Here’s the link to my website 449.f81.myftpupload.com