How is Bootstrap library related / configured for my HTML to use?

Tell us what’s happening:

I am interested in how the Bootstrap library configured to allow the classed to be accessed in my HTML.

(ie there is no statement as is used to access the style sheet.

Your code so far

<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
<style>
  .red-text {
    color: red;
  }

  h2 {
    font-family: Lobster, Monospace;
  }

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

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

  .smaller-image {
    width: 100px;
  }
</style>

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

  <p>Click here for <a href="#">cat photos</a>.</p>

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

  <img src="https://bit.ly/fcc-running-cats" class="img-responsive" alt="Three kittens running towards the camera. ">
  <button class="btn btn-block btn-primary">Like</button>
  <button class="btn btn-block btn-info">Info</button>
  <button class="btn btn-block btn-danger">Delete</button>
  <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 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.84 Safari/537.36.

Link to the challenge:
https://www.freecodecamp.org/challenges/use-the-bootstrap-grid-to-put-elements-side-by-side

For the challenges, the bootstrap library is included in the background. It’s basically just one huge CSS file with preconfigured classes and other style rules.

so it doesn’t require a reference set up in my html ? or is it referenced by the css link ?

If you’re going to start from scratch you’ll have to add it yourself. Here’s a <link> for it:

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">

Thanks. That helps. In my past experience I’d have set up all the sheets referenced.