CSS Animation Events

transitionendEvents.js

element.addEventListener('transitionend', function(e) {
  let prop = e.propertyName.match(/border-(.*)-color/);
    
  if (prop[1]) {
    console.log(`Border color for ${prop[1]} transitioned`);
  }
});

element.addEventListener('transitionend', function(e) {
  if (e.propertyName === 'border-top-left-radius') {
    console.log(`border-radius transitioned`);
  }
});