I went to CSS-Tricks, my go-to web forum for anything code related, to ask about adding a custom class to specific pages. I want all of my galleries (and there'll be a lot of 'em) to be formatted exactly the same way. So, if I were to say have the word "gallery" applied as a class to each gallery page, then I could target all of my galleries in one fail swoop while writing my CSS. I was personally looking for a way to do it with pure PHP, but someone suggested I create a child template called "gallery." I searched Google for any instructions on creating child templates, but all that came up were articles discussing "child themes," which isn't what I want. So, figuring that the "Default Template" is probably being running off of the index.php file, I copied that code and added the code necessary to make it a separate template and used FileZilla to add the custom template to the theme. I figured that would do the job, and the page loads just fine, but it looks nothing like it did when I had the "Default Template" selected. Any and all help will be muchly appreciated.

And I tried using the "Portfolio" template, but I much prefer the way it looks when you use the "Default Template" and use the Visual Composer to insert a full-width portfolio.

That helps me somewhat so I don't mess with the actual theme, but I still need to know which file is being used for the "Default Template." I'm simply trying to replicate the default template, give it the name "gallery," and then use the renamed template for my galleries so all of them have a class of "gallery" in the output for the body.

This is what it looks like if I use index.php as a base for my gallery template, which is horrendous in comparison to the second image, which is using the Default Template. But the default template is used for the majority of my pages and I would like to be able to target my galleries specifically.

Awesome. Thank you. Duplicated page.php and added the template code to the top, renaming it to "gallery," and it works like a charm!