Hi Dana-Marie,
Hope you are well!
I got this checked and the section background is not responsive in Flex. You can use a solid background color for the section and use an image widget on top with the banner graphics which has the text in the image. Or, you can use a gradient or the graphic image as a section background so even if it cuts, it only cuts the graphic and add an image on top which has a text.
Additionally, we do have an option to use a code to make sure that the header is responsive across all devices, however, that can be done by our HTML team and it will be an additional cost to use CSS.
I hope this helps Please let us know if you have any further questions.
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Raashi Semwal Khati
Senior Quality Analyst
Cvent
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