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HTML

CSS

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HTML

              
                <p>Hover over each box for 1s. Once the border has finished changing color, the background-color should be changed to red.</p>

<p>Using <code>transition: none;</code> prevents <code>transitionend</code> event from being fired.</p>


<div class="box">Border changes for 1s, then background changes after anim </div>
<div class="box no-anim">Border instant, background never changes</div>
<div class="box short-anim">Border instant, background instant</div>
              
            
!

CSS

              
                .box {
  border: solid 6px;
  transition: border-color 1s;
  
  width: 100px;
  height: 100px;
  margin: 20px;
  padding: 8px;
}

.box:hover {
  border-color: blue;
}

.no-anim {
  transition: none;
}

.short-anim {
  transition-duration: 0.01s;
}
              
            
!

JS

              
                let boxes = document.querySelectorAll('.box')

boxes.forEach(box => {
  box.ontransitionend = () => {
    box.style = 'background-color: red'
  }
})
              
            
!
999px

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