<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
  <div class="container-1">
    <h1>Challenge 1:Age in days</h1>
    <div class="flex-box-container-1">
      <div>
        <button class="btn btn-primary" onclick="ageInDays()">Click Me</button>
      </div>
      <div>
        <button class="btn btn-danger" onclick="reset()">Reset</button>
      </div>
    </div>
    <div class="flexbox-container-1">
      <div class="finalResult">
        <h2 id="finalResult"></h2>
      </div>
    </div>
  </div>
  
  <div class="container-2">
    <h1>Challenge 2:Cat Generator</h1>
    <div class="flex-box-container-2">
      <img src="" alt="gif">
      <div>
        <button class="btn btn-success">Generate Cat</button>
      </div>
    </div>
  </div>
</body>
</html>
.container-1{
  border: 3px solid black;
  padding: 5px;
}

.flex-box-container-1{
  display: flex;
  border: 3px solid black;
  padding: 5px;
  justify-content: space-evenly;
}

.container-2{
  border: 3px solid black;
  padding: 5px;    
}
.flex-box-container-2{
  display: flex;
  border: 3px solid black;
  justify-content: space-evenly;
  padding: 5px; 


// age in days

function ageInDays() {
  var birthYear = prompt('Please enter your birth year')
  var ageInDay = (2020 - birthYear) * 365;
  var h1 = document.createElement('h1');
  var finalResult = document.createTextNode('You are ' + ageInDay + ' days old');
  h1.setAttribute('id','ageInDays');
  h1.appendChild(finalResult);
  document.getElementById('finalResult').appendChild(h1);
 }

function reset() {
 document.getElementById('ageInDays').remove(); 
}

External CSS

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External JavaScript

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