my site https://www.elektrolinka.cz/ has a poor core web vitale score on mobile devices. The main page scores 5.3 seconds in FCP metrics. Really don’t know what to do. I am using compressed WebP and AVIF images, minified CSS, running the site through Cloudfare and lazy load Tag manager using a script detecting the user scroll, then loading the rest of the codes on the site. Still the performance is bad. Help, please.
I tried reducing the font size on the main page and the logo size, also tried downloading the fonts instead of using Google fonts. However, nothing helped.