This file looks like it knows a lot about two things:

1. The DOM (and several discrete sections of the DOM)
2. How to save stuff to your server. 

This indicates that this single file is highly coupled to the rest of your code base. A change on the server structure would result in a change to this file. A change to the HTML will result in a change to this file. When designing applications, it's worth spending a moment thinking about "How many files will force me to change this file if I change those files?" as a metric of coupling. If the answer is > 1~2 you may want to consider splitting the code into separate responsibilities.