Hi @elzbru
I understand what you mean and simply copying and pasting the code from GetResponse (or any other ESP) can have the same issue.
It’s because those shortcodes use CSS and within most HTML files, they also use CSS, which can conflict with the style of how your opt-in form/box will look.
You can really only fix this if you know CSS or hire someone who can do this for you. I do know it would only be a very small change (or adding) within your CSS file on your sales/squeeze page.
I hope this helps.
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