I froze header but page is shifting and causing CLS issues I think

[sdemeter2]

I froze the header on my website, but when you land on a page the main content shifts down. I think this is causing a CLS issue with google and I am hoping someone can help me pad the main content section or adjust the header.liquid so that shift doesn't happen right when you land on a page. 

www.thecarpetstoreinc.com

Thanks

Steve