Having problem with img src

Tell us what’s happening:

Your code so far

<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>


  h2 {
    font-family: Lobster;
  }

  p {
    font-size: 16px;
    font-family: ;
  }

  .thick-green-border {
    border-color: green;
    border-width: 10px;
    border-style: solid;
    border-radius: 50%;
  }


  }
</style>

<div class="container-fluid" >
  <h2 class="text-primary text-center">CatPhotoApp</h2>


  <img src="https://bit.ly/fcc-relaxing-cat"class="image-responsive thick-green-border" alt="A cute orange cat lying on its back.">

  <img src="https://bit.ly/fcc-running-cats" class="img-responsive" alt="Three kittens running towards the camera. ">
  <div class="row">
    <div class="col-xs-4">
      <button class="btn btn-block btn-primary">Like</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-info">Info</button>
    </div>
    <div class="col-xs-4">
      <button class="btn btn-block btn-danger">Delete</button>
    </div>
  </div>
  <p>Things cats love:</p>
  <ul>
    <li>cat nip</li>
    <li>laser pointers</li>
    <li>lasagna</li>
  </ul>
  <p>Top 3 things cats hate:</p>
  <ol>
    <li>flea treatment</li>
    <li>thunder</li>
    <li>other cats</li>
  </ol>
  <form action="/submit-cat-photo">
    <label><input type="radio" name="indoor-outdoor"> Indoor</label>
    <label><input type="radio" name="indoor-outdoor"> Outdoor</label>
    <label><input type="checkbox" name="personality"> Loving</label>
    <label><input type="checkbox" name="personality"> Lazy</label>
    <label><input type="checkbox" name="personality"> Crazy</label>
    <input type="text" placeholder="cat photo URL" required>
    <button type="submit">Submit</button>
  </form>
</div>

Your browser information:

Your Browser User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36.

Link to the challenge:
https://www.freecodecamp.org/challenges/ditch-custom-css-for-bootstrap

Hello and thank you, I found out that when using code pen one must use a photo app like imgur to store the photos. Storing photos in your computer and linking it to codepen does not work.
That is what I was having problems with