Footer: Reduce padding on footer elements
To tighten up the spacing and padding on footer elements you can use this code reference and customize to your needs.
Result:

Before:

Code:
/* -- code to reduce padding in footer elements -- */
/* tightens top/bottom, left/right padding */
.wrapper.site-footer {padding: 10px;}
/* margin after main columns */
ul.footer-quicklinks li {margin-bottom: 5px;}
/* padding above the copyright links */
ul.footer-secondary li {margin-top: 0px;}
/* social and payment icons */
ul.footer-social li, ul.footer-payment li {margin-top: 10px;}
/* - end - */
Mobile
You can also add this additional code to reduce spacing on mobile.
Result:

Additional mobile code:
/* -- code to tighten mobile spacing in footer -- */
@media screen and (max-width: 769px) {
.footer-social,.footer-payment {
margin:0px;
}
}
/* - end - */
Where do I add the code?
Use this link to learn where exactly to add this code snippet: