Website built from site builder not fitting screen.

I don’t know if anyone knows how to fix this here, but the website I have build from the site builder in the CPanel does not fit the internet browser screen. Does anyone know what can cause this and how it can be fixed? To see the problem, the link is:

The best way to fix it is to drop the old SiteReptile builder and switch to the SitePro builder (you can find it in your client area). The templates from SitePro look fresh and modern and can be customized for different screen sizes, from smartphones to 4K monitors and TVs. Be sure to try it!

Thanks, I will do that.