When you visit crx.clever.com, the first thing you notice is that nothing loads. The server returns a 404 error page. That alone makes it hard to recommend trusting this site for anything, because there's nothing to evaluate.
Beyond that, there are deeper problems. The domain registration is completely hidden from public WHOIS records. That is unusual and means the people behind this site are actively concealing their identity. There is also no privacy policy, no terms of service, no contact information, and no about page on the site itself.
Crx.clever.com appears to be associated with Clever, an education platform used by schools. If you are a teacher or administrator trying to reach Clever, this subdomain is not the right way. School IT systems should verify that any Clever-related URLs are properly documented by the company. For a service that could handle student data, the lack of transparency and broken site are serious warning signs.
A legitimate service in this space would have clear ownership, working pages, and proper legal disclosures. Crx.clever.com has none of those. Until those issues are resolved, treat this domain with extreme skepticism.