Mobile site not viewing

Hi,

We have just setup this new theme and it is displaying on all browsers for PCs/Macs but not viewing from Mobile devices.

Background: We originally had our site setup in Weebly but have now installed WordPress and installed the theme.

To get this site going on I had to rename the index.html and it then displayed the new site and respective php files but it is still showing the old site on Mobile devices.

the website is http://www.foodandbeveridge.com

Can you advise on how I can the new site to work properly on Mobile devices?

Kind Regards
Sean