Try clearing your browser cache.
Usually when you can connect OK using your phone, you're connecting with a different network. Using your home PC you're using your ISP internet network, so that might be the problem there.
If you could not connect with your phone then one could say you can't connect via two different networks so the site must be down. But that isn't the case here. If this persists you should call your ISP and see if they are blocking the site for some reason.