I designed a page layout that is responsive and adjusts fine to smaller screens, but when I added in a code block (and used highlight.js to format it), the responsiveness breaks. The code box and text content both spill over the width of the device and you have to scroll back and forth. Ideally, the code block should have its own scroll bar to view the code, but the content still adapts. I've tried playing around with different attributes of the flexbox that contains the content, but it still breaks the layout.
If I comment out both .article-container and article the page adjusts fine, but if either one of them is present it breaks. Also, if I leave the CSS as is and comment out the code block it's responsive.
The content in fullscreen mode
How mobile looks without CSS - the code box scrolls like it should, but the rest of the page adapts
Note that 2 is also how the site looks with CSS and without the codeblock. So something about the way they are interacting is breaking.