JSFiddle - React, Tailwind, and code Playground

by Maxim Ivanov

HTML

<form id="formElement">
    One: <input type="text"><br>
    Two: <input type="text">
</form>

CSS

.focused {
    outline: solid 2px red;
}

JavaScript

// returns NodeList
var input_list = document.querySelectorAll('#formElement input'); 
// converts NodeList to Array
var input_array = Array.prototype.slice.call(input_list); 

input_array.forEach(function(input){
	
  input.onfocus = function(){
  	this.classList.add('focused');
  }
  
  input.onblur = function(){
  	this.classList.remove('focused');
  }
  
})