Using with child themes

My web site is built using a child theme (a child theme of the popular Stack theme, created by Tom Rhodes). I need to insert the Facebook pixel into the top navigation header in my site. Can I use your Easy custom JS & CSS plug-in to do this?

I am concerned about this particular paragraph in your guidance text:

“If you don’t use a child theme and need to insert some customizations, you can take advantage of the inbuilt editor and easily create and insert custom css and js code into the header or footer. Once the code is saved, it immediately influences the workings of your site.”

The page I need help with: [log in to see the link]