HTML5, Sass and JavaScript

This was the first time I used local storage(and just a little bit of sortablejs) and to be honest I learnt a lot(even though my code is ..not upto the mark). But there is stuff that I'm not able to figure out such as- when I switch to active or completed state how do I set the first element in each to be of a border radius. I'm not really sure how to go about that so if anyone can help I'll be really grateful. Thanks! (I came across this weird behaviour, I don't know why its not working on mobile the way its supposed to)