Amp Validation Error

Hello,
I have converted my entire site into amp and while checking for validation error, i get this error on all pages: “The author stylesheet specified in tag ‘style amp-custom’ is too long – we saw 75027 bytes whereas the limit is 50000 bytes.”
I have eliminated all the additional css and cut down the css to a limit and even minified the css but still it is not matching the limit. I cannot remove any more css as the pages will not look properly then.

Here is the site url for your reference: https://wordpre1.wwwss43.a2hosted.com/sprint-insights/amp/

Need help regarding this issue.

Thank you.

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