Do you have a link to your Site? Because that depends on how you’re adding your code in. Everything is supposed to be automatically responsive when added to the theme, but there are certain cases where if you add something and the code you add can override or break the responsive css features. In order to know I would need a link to your site and the page that the divs are located on (also let me know which divs you’re referring to as well). Once you post that then I (or anyone else that sees this) will be able to figure out what could be going on.
Also, if you’ve added custom CSS, sometimes depending how it’s added, it can override/interrupt the default responsive features. To prevent that from happening the code would have to follow the “Responsive CSS Guidelines” which every site regardless of the theme you’re using would have to follow in order to work properly (even on other platforms). I’ll probably be able to see what’s going on once I can take a look, I just need to see it first.
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