Hi,
Can you share me your Big-Commerce website URL..?
I have 10+ years Exps. in Big-Commerce and all PHP framworks with javascript/jQ/Css3.
We also done Theme Customization,Responsive,SEO friendly,Shipping,Payment Gateway,Shopping cart,Multiple languages,Automatic taxes,Email templates,Social
media integration,Product organization,Check Out.
Regards
Sonu kalra