Why is my tumblr-hosted website showing me a broken layout on Firefox? [closed]

I have a Tumblr Blog that has a custom layout made up of HTML, CSS, and JS. It’s displaying properly on Chrome and Safari web browsers on both PC and mobile, but as soon as I open the same page on Firefox (and Firefox Developer Edition) it magnifies everything on the page to the point that it’s not easily viewable anymore.

I thought the problem was needing a "word-wrap: break-word;" addition in an element to target the specific text post that’s causing the issue, but that doesn’t seem to fix it. Any other debugging I’ve tried so far was in completely removing all the included Javascript to see if anything related to the added scripts was causing this underlying effect to take place in Firefox alone, but to no avail. I also tried targeting and removing + later modifying the @-moz-document url-prefix() {} element since it directly ties the containers to display changes in Firefox, but any changes to the height and width of the container through that element or edits to how text should work didn’t render any fixes.

Any help in narrowing the problem down to target and fix whatever is causing its entire layout to break, so that it displays properly again on Firefox, would be greatly appreciated!

The website | The code