Site won’t open

I’m trying to open my site, and it simply won’t open. It’s apparently loading, but it won’t go beyond google’s homepage and it just keeps loading with the little circle in the tab going round and round.

After 3 minutes or so, it says: Gateway Timeout
The gateway did not receive a timely response from the upstream server or application.

Can anyone help fix please?

I would be incredibly grateful.

Best regards,

The page I need help with: [log in to see the link]