The buy button, variant pickers, etc in the Sticky Buy Now Button bar look funny or are the wrong size

This happens when Sticky Buy Now Button is unable to override the theme styles of the elements copied from your product page. 

If you do not have HTML / CSS experience, please contact support for assistance. 

If you do, try adjusting the CSS of the elements in question. Your custom CSS can be added to the app via the Custom CSS field in the Advanced Settings section of the app.