Hi Anuj,
I have replied to your other forum where you asked this question as well, take a look here - https://ecommerce.shopify.com/c/shopify-discussion/t/how-to-remove-signup-popup-in-icon-theme-410884....
Another note, is that all theme's have a mobile view which is different to the desktop view. The reason for this is because with more and more shopping being done on mobile devices, it's important to have an online store that looks just as great on a smart phone as it does on a computer monitor. Which is why each theme has their own, fully functional, mobile version.
This way, it makes it much easier for customers to navigate and shop on your site via mobile.
