Adapted from a Traversy Media vanilla JavaScript tutorial on YouTube: https://www.youtube.com/watch?v=7l-ZAuU8TXc&list=PLillGF-RfqbbnEGy3ROiLWk7JMCuSyQtX&index=8
Brad's project code: https://codepen.io/bradtraversy/pen/jGNWey
Link to deployed app: https://loosenthedark.github.io/unit-converter/
NB: The vanilla JS code used in this initial version is (probably) quite bulky and long-winded. It is my intention at this point to return to it in due course and refactor wherever necessary to eliminate redundant code blocks and make it more concise.