DOM / pure JavaScript solution to jQuery.closest() implementation?

Answer 1

In this case, use JavaScript's closest()

Exemple:

var el = document.getElementById('div-03');

var r1 = el.closest("#div-02");  
// returns the element with the id=div-02

var r2 = el.closest("div div");  
// returns the closest ancestor which is a div in div, here is div-03 itself

var r3 = el.closest("article > div");  
// returns the closest ancestor which is a div and has a parent article, here is div-01

var r4 = el.closest(":not(div)");
// returns the closest ancestor which is not a div, here is the outmost article

  
Here is div-01
    
Here is div-02
      
Here is div-03
    
  

You can find more information, on MDN Web Docs by clicking here