Profile: sksoni

I am using Emporium theme in Nopcommerce 4.3. In that category page at windows view screen shows the add to cart button while the same page I am open in mobile view at that time add to cart button is not showing.

For more clear, lets see the image,

Windows View
https://i.stack.imgur.com/VNKc4.png

Mobile View
https://i.stack.imgur.com/yzscQ.png

Note : I installed 3 plugin named,
1. Seven Spikes Core
2. Nop Ajax Cart
3. Nop Emporium Theme

I want to change the fontsize as well as fontfamily of whole word. From where I can change it?