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  <section class="calc">
    <form class="form" id="form">
      <h1>Número quadrado perfeito</h1>
      <label for="num">Digite o número</label>
      <input id="num" type="number"/>
      <button id="button">Verificar</button>



                @import url(",400i,700");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;

body {
  font-family: Lato, sans-serif;
  font-size: 20px;

.calc {
  min-height: 100vh;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
  background-color: #FFEBEE;
  box-shadow: 0px 0px 30px gray;

.calc h1 {;
  padding-top: 0.4em;
  text-align: center;

.form {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  padding: 1em;

.form label,
.form button {
  margin-top: 1em;
  padding: 1em;

.form input,
.form button {
  font-size: inherit;
  font-family: inherit;
  width: 100%;
  padding: 0.5em;

.form button {
  background-color: #FBEFFF;
  cursor: pointer;
  border-radius: 0.3em;
  width: 50%;

.form button:hover {
  filter: opacity(0.8);

.form button:active {
  background-color: #FCF;
  color: #000;
  filter: opacity(0.8);


                function calcularQuadradoPerfeito (num) {
  //retira a raiz quadrada, valor inteiro
  const raizQ = parseInt(Math.sqrt(num));
  //verifica se a raiz quadrada elevado ao quadrado é um valor exato
  return (raizQ * raizQ) == num;

function validaEntrada (num) {
  if(num == "" || num <= 0){
    return false;
  return true;

const botao = document.getElementById('button');

const form = document.getElementById('form');

form.addEventListener('submit', function(event) {
  const value = document.getElementById("num").value;

    alert('Insirar algum número maior que zero');
  }else if(calcularQuadradoPerfeito (value)){
    alert('É Quadrado perfeito');
    alert('Não é quadrado perfeito');