freeCodeCamp/curriculum/challenges/chinese/03-front-end-development-libraries/bootstrap/center-text-with-bootstrap.md

---
id: bad87fee1348bd8acde08812
title: 用 Bootstrap 居中文本
challengeType: 0
forumTopicId: 16771
dashedName: center-text-with-bootstrap
---

# --description--

可以使用 Bootstrap 将顶部的元素居中来美化页面。 只需要将 `h2` 元素的 class 属性设置为 `text-center` 就可以实现。

记住：可以为一个元素添加多个 classes ，class 间通过空格分隔，就像这样：

```html
<h2 class="red-text text-center">your text</h2>
```

# --hints--

应使用 `text-center` class 将 `h2` 元素居中。

```js
assert($('h2').hasClass('text-center'));
```

`h2` 元素应具有 `red-text` class。

```js
assert($('h2').hasClass('red-text'));
```

# --seed--

## --seed-contents--

```html
<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">CatPhotoApp</h2>

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

  <a href="#"><img class="smaller-image thick-green-border" src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/relaxing-cat.jpg" alt="A cute orange cat lying on its back."></a>

  <img src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/running-cats.jpg" class="img-responsive" alt="Three kittens running towards the camera.">
  <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="https://freecatphotoapp.com/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>
```

# --solutions--

```html
<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://cdn.freecodecamp.org/curriculum/cat-photo-app/relaxing-cat.jpg" alt="A cute orange cat lying on its back."></a>

  <img src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/running-cats.jpg" class="img-responsive" alt="Three kittens running towards the camera.">
  <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="https://freecatphotoapp.com/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>
```