Pomodoro Timer Finally Finishing Up

Mostly done with Pomodoro Timer. Critiques please? I was planning on adding audio and a gradient to it tomorrow. On another note, I noticed there’s an issue where if I click on a button multiple times at a fast pace that the text gets outlined. How do I prevent this from happening?

It sticks at 0:01 second.

I wrote the JavaScript for this project on brackets. And the timer works just fine on live preview as in it will go to the next session (break/session), not sure why it’s sticking on codepen. Never mind it should work now, the HTML was different on codepen.