I´m trying to get the Pinterest save buttom running on all the images with this script on my site
<script async defer src="//assets.pinterest.com/js/pinit.js"></script>
The thing is that it works on the desktop version and it looks ok, small, well put on the upper left corner on every image when I hover like this: 
But on the mobile version the scale of the save icon gets bigger for some reason and it ends up looking like this: 
Is there a way to correct this or to disable a js on a mobile device?
By the way i´m currently running BootStrap and a lightbox js on the site too in case there is some known Issues between those and pinterest.
Thanks!