Yeah it supposed to work the way you have it, but for some reason your custom css is overriding the main css. How did you add that css? Is it a file, or from the Genesis Theme Settings….or a plugin?
Maybe if you add !important to the responsive section it will have priority when in mobile view……You don’t usually have to do this, but it could be a quick solution that will get the job done if you don’t have much time.
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