Dynamic content update in affix block (Twitter Bootstrap 3)?

Question

Bootstrap

There is a block that, when scrolling, is fixed from the top - this is the name of the region in this case, "Russia". How can I dynamically update the content of this block when the user scrolls the page to "Germany", how do I update the block and replace the country with the one that is pulled up from the bottom? That is, they reached Russia - they fixed it from above, scrolled to Germany - they updated the block - Germany became instead of Russia (see screenshot.)