NET::ERR_CERT_AUTHORITY_INVALID https in red color
If it's not self-signed then one of certificates in your ssl certificate chain may use vulnerable encryption algorithms like SHA-1. Check what encryption each certificate uses (you may do it on PC). Probably you will need to find ssl registrator which does not uses old encryption algorithms.you may use https://www.ssllabs.com/ssltest/ to check if your site has issues with SSL configuration or certificate itself.
In fact i just checked it and here's result http://i.imgur.com/X9dPX8Q.jpg . The vulnerabilities it output could be the reason why mobile chrome is not trusting the certificate and shows you warning.
Another possible issue is man in the middle attack on your device. What network are you using? is it the same as your PC network? if not, it could be mitm attack on you.