Ditch Custom CSS for Bootstrap

说明：

现在，让我们清理一下之前的代码了，以让我们的 Cat Photo 应用看起来更简洁，用 Bootstrap 内置的样式来替换我们之前自定义的样式。

别担心 —— 以后我们会有大把时间来自定义我们的 CSS 样式的 ：）

删除 style 元素里的 .red-text, p 和 .smaller-image CSS声明，这样你的 style 留下的声明就只有 h2 和 thick-green-border。

然后删除包含死链接的 p 元素。 移除 h2 元素的 red-text class 并且用 Bootstrap的 text-primary class替换之。

最后，移除第一个 img 元素的 "smaller -image" class ，替换为 Bootstrap的 img-responsive class。

原始代码：

<link href="//fonts.gdgdocs.org/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="/images/relaxing-cat.jpg"></a>

  <img src="/images/running-cat.jpg" class="img-responsive">
  <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>

调试代码：

<link href="//fonts.gdgdocs.org/css?family=Lobster" rel="stylesheet" type="text/css">
<style>


  h2 {
    font-family: Lobster, Monospace;
  }

  p {
    font-size: 16px;
  }

  .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>

  <a href="#"><img class="img-responsive thick-green-border" src="/images/relaxing-cat.jpg"></a>

  <img src="/images/running-cat.jpg" class="img-responsive">
  <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>