Id advise a little revision of the tutorial as right now there are some steps missing when following it e.g. Outlook. This allows us to subtract two times from each other and get the amount of time in between. That should be good.. @JDrake corrected the mistake. Whats that length? In head section it connects to the style.css using tag and in body section it connects to script.js file using
javascript countdown timer minutes seconds codepen