@davidjosephl the CTA previewer is just showing what the button will look like without any other styles applied. In this case, if the button looks different on a live page it is likely due to a conflict with something in your style-sheet attached to the page that you're using. If you could link to the preview link of the page here, I'd be happy to give this a closer look.
Remember, ALL 'previews' are approximations of what browsers will see. There are literally GOBS [good word] of browser versions that have simply not been allowed for in 'preview' view.
Consider, Firefox is pretty stable, but Chrome and MS Edge update so often we stopped keeping track. There is no substitute for actually viewing the page/email in the actual browser.
Forget 'preview' mode and go to the actual browser ... it will make your life much easier.
Problem solved.
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