AMP Errors: External stylesheets not supported

Hi,

I have noted the following errors on google webmaster tools with respect to AMP:

External stylesheets not supported, except for whitelisted font providers. Use the document inline ‘style amp-custom’ tag instead.

A total of 138 pages are affected by each of these errors. Can someone please provide me with some guidance on how to fix it?

URL:- https://wikibioinside.com/shivangi-joshi-wiki-bio-husband-age-family-height-weight-net-worth/amp/
I appreciate your help!