Hi Lauren,
Sharing my experience here as I spent quite a bit of time exploring this feature as well.
In my opinion CVENT didn't make it very clear that this feature isn't really for custom HTML / CSS styling on these pages. For that you'll need to wait for Advanced Coding Mode (CSS) - Planned for Q4 2020 as of now.
This is because the new code widget places the actual code inside of an iFrame. The iFrames with the code wouldn't interact with the rest of the website. So you can't style using this feature.
"You can use code widget to create custom standalone sections, build tables, add accordions, have custom galleries, animations etc. However, you cannot use it to change anything on the existing website elements." - CVENT Support
I've only used the code widget so far to place Facebook tracking pixels on my registration pages. I couldn't place these pixels with code snippets because of the way it automatically adds script tags in FLEX, as Facebook pixels are a combination of Javascript and HTML.
Hope this helps.
Best,
Evan
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Evan Ring
Senior Operations Manager
Dow Jones & Co., Inc
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