Heyo. First off: I'm not code-savvy. I can sort of patchwork things together, which is what I've been doing, but I have no formal education on the topic and I'm far from well versed in what I'm doing. BUT I cooked up a customized system for a game I'm running, wanted to consolidate all gameplay to a single program, so figured I should just suffer my way through figuring out a character sheet. To reiterate: I'm not using an existing system. I've borrowed the template from Adventurers Revised Edition as a starting point to work off of simply because it seemed the most straightforward for my needs, and I've been working on reshaping it for my stuff for the past several days. Really all I've been doing is shaving away the content I don't need, reformatting what I want, and using resources like this to, again, patchwork in any new content. I understand this is probably a bizarre way of doing things and I might make more code-efficient people cry, but it's what I have to work with and I'm okay with it not being super professional. BUT I digress. I've actually been doing fairly okay with this strategy so far, but I've run into an issue and all my ideas for troubleshooting have gone nowhere, so I guess it's time to finally ask for help. What I have: I feel fairly good about what I've accomplished, all things (including my incompetence) considered. What I want: See those tabs in the middle of the sheet? I'd like them to operate, you know, like tabs. You should be able to glean just by looking what my intention is. My problem: I've tried the tab code from Roll20's own resources . I've tried tab codes that Google gave me from W3Schools . Neither work. They don't work in the sheet preview and they don't work in-game. But the fucky part: they do work in jsfiddle . (Both of those gifs, despite the aesthetic differences, are the exact same code being used.) What do I mean by them not working? They exist there as you see in the above screenshot, but clicking does nothing. All the tabs' contents are visible beneath, like one continuous page, instead of separated. It would be one thing if the code just didn't work at all, but the fact that it works elsewhere but not in Roll20's system has me scratching my head. I wonder if there's something else in my sheet's code that would interfere, but again, I'm not a coder, so I don't really know where to look. Any help would be deeply appreciated, since I can't find any relevant info or any existing known bugs or anything like that. I'm positive this is user error since I don't know what I'm doing, but again, no idea where to even look for the problem at this point. Assuming it'd be helpful, here's the HTML and CSS I have so far. And please--I'm sure it's a mess, I'm sure there are egregious ugly aspects to it; I'm not here to get roasted about my shoddy coding, and it's a work in progress that I haven't even attempted to refine yet, so please be civil lmao. Thanks in advance!!