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                <h1 id="title">Puppy Facts</h1>
<p id="first-fact">They spend 15–20 hours a day sleeping.</p>
<p id="second-fact">Puppies can be twins!</p>
<p id="third-fact">Puppies become 'adults' when they turn one.</p>
<img src="" alt="Sweet puppy sleeping">
<!-- step 1: create button -->
<button id="change-btn">change everything!</button>

<!-- FOR SPICY CHALLENGE: new button - change FACTS -->


                img {
  height: 150px;


                var pageTitle = document.getElementById('title');
var firstFact = document.getElementById('first-fact');
var secondFact = document.getElementById('second-fact');
var thirdFact = document.getElementById('third-fact');

// variable for button
var changeBtn = document.getElementById('change-btn');

// listen
changeBtn.addEventListener("click", function() {
  //  code that you want to run once button is clicked

//listen to second button