As I have mentioned, this is Not a theme issue.
You cannot disable W3 Total Cache plugin and expect it to stop loading cache content.
It will continue to load cache content, you need to disable it in the settings.
I had login to your website, and added the custom css codes that I had provided in my previous reply.
Purge your W3 Total Cache’s cache content and it’s working now.
This is screenshot of your header taken from my iPhone.
This is screenshot of your footer taken from my iPhone.
This is screenshot of your webpage source code show the custom css codes that I had added.