JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="text_area"></textarea>
<input type="time" class="asd"/>


<div class="expired-time">
<input type="number" class="hour" max="24" min="0" value="23">
<span>:</span>
<input type="number" class="minute" max="60" min="0" value="42">
<span>:</span>
<input type="number" class="second" max="60" min="0" value="52">
</div>

CSS

input{
  padding: 10px 15px;
}

.expired-time input{
  max-width: 50px;
}

JavaScript

$('#text_area').on('keyup paste', function() {
    console.log('called');
});
var a = $(".expired-time").children("input").length;
console.log($(".expired-time").children("input").length);
console.log($(".expired-time").children("input").val())
var asd;
for (var i = 0; i < a; i++) {
	if(asd){
	  asd = asd + '/' +  $(".expired-time").children("input").val();
  } else {
  	$(".expired-time").children("input").val();
    debugger
  }
}

console.log(asd)