2018-10-10 18:03:03 -04:00
|
|
|
|
---
|
|
|
|
|
id: 587d7fa5367417b2b2512bbd
|
|
|
|
|
title: Extend One Set of CSS Styles to Another Element
|
|
|
|
|
challengeType: 0
|
2020-09-07 16:11:08 +08:00
|
|
|
|
forumTopicId: 301456
|
2018-10-10 18:03:03 -04:00
|
|
|
|
localeTitle: 将一组CSS样式扩展到另一个元素
|
|
|
|
|
---
|
|
|
|
|
|
|
|
|
|
## Description
|
2020-09-07 16:11:08 +08:00
|
|
|
|
<section id='description'>
|
|
|
|
|
Sass 有一个名为<code>extend</code>的功能,可以很容易地从一个元素中借用 CSS 规则并在另一个元素上重用它们。
|
|
|
|
|
例如,下面的 CSS 规则块设置了<code>.panel</code>class 的样式。它有<code>background-color</code>,<code>height</code>和<code>border</code>。
|
|
|
|
|
|
|
|
|
|
```scss
|
|
|
|
|
.panel{
|
|
|
|
|
background-color: red;
|
|
|
|
|
height: 70px;
|
|
|
|
|
border: 2px solid green;
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
现在你需要另一个名为<code>.big-panel</code>的面板。它具有与<code>.panel</code>相同的基本属性,但还需要<code>width</code>和<code>font-size</code>。
|
|
|
|
|
可以从<code>.panel</code>复制并粘贴初始 CSS 规则,但是当你添加更多类型的面板时,代码会变得重复。
|
|
|
|
|
<code>extend</code>指令是一种重用为一个元素编写的规则的简单方法,然后为另一个元素添加更多:
|
|
|
|
|
|
|
|
|
|
```scss
|
|
|
|
|
.big-panel{
|
|
|
|
|
@extend .panel;
|
|
|
|
|
width: 150px;
|
|
|
|
|
font-size: 2em;
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
除了新样式之外,<code>.big-panel</code>将具有与<code>.panel</code>相同的属性。
|
|
|
|
|
</section>
|
2018-10-10 18:03:03 -04:00
|
|
|
|
|
|
|
|
|
## Instructions
|
2020-09-07 16:11:08 +08:00
|
|
|
|
<section id='instructions'>
|
|
|
|
|
创建一个扩展<code>.info</code>的 class<code>.info-important</code>,并将<code>background-color</code>设置为洋红色。
|
|
|
|
|
</section>
|
2018-10-10 18:03:03 -04:00
|
|
|
|
|
|
|
|
|
## Tests
|
|
|
|
|
<section id='tests'>
|
|
|
|
|
|
|
|
|
|
```yml
|
|
|
|
|
tests:
|
2020-09-07 16:11:08 +08:00
|
|
|
|
- text: <code>info-important</code>class 应该将<code>background-color</code>设置为<code>magenta</code>。
|
2020-02-18 01:40:55 +09:00
|
|
|
|
testString: assert(code.match(/\.info-important\s*?{[\s\S]*background-color\s*?:\s*?magenta\s*?;[\s\S]*}/gi));
|
2020-09-07 16:11:08 +08:00
|
|
|
|
- text: <code>info-important</code>class 应使用<code>@extend</code>继承<code>info</code>class 的样式。
|
2020-02-18 01:40:55 +09:00
|
|
|
|
testString: assert(code.match(/\.info-important\s*?{[\s\S]*@extend\s*?.info\s*?;[\s\S]*/gi));
|
2018-10-10 18:03:03 -04:00
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Challenge Seed
|
|
|
|
|
<section id='challengeSeed'>
|
|
|
|
|
|
|
|
|
|
<div id='html-seed'>
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<style type='text/sass'>
|
|
|
|
|
h3{
|
|
|
|
|
text-align: center;
|
|
|
|
|
}
|
|
|
|
|
.info{
|
|
|
|
|
width: 200px;
|
|
|
|
|
border: 1px solid black;
|
|
|
|
|
margin: 0 auto;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</style>
|
|
|
|
|
<h3>Posts</h3>
|
|
|
|
|
<div class="info-important">
|
|
|
|
|
<p>This is an important post. It should extend the class ".info" and have its own CSS styles.</p>
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
<div class="info">
|
|
|
|
|
<p>This is a simple post. It has basic styling and can be extended for other uses.</p>
|
|
|
|
|
</div>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Solution
|
|
|
|
|
<section id='solution'>
|
|
|
|
|
|
2020-09-07 16:11:08 +08:00
|
|
|
|
```html
|
|
|
|
|
<style type='text/sass'>
|
|
|
|
|
h3{
|
|
|
|
|
text-align: center;
|
|
|
|
|
}
|
|
|
|
|
.info{
|
|
|
|
|
width: 200px;
|
|
|
|
|
border: 1px solid black;
|
|
|
|
|
margin: 0 auto;
|
|
|
|
|
}
|
|
|
|
|
.info-important{
|
|
|
|
|
@extend .info;
|
|
|
|
|
background-color: magenta;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</style>
|
|
|
|
|
<h3>Posts</h3>
|
|
|
|
|
<div class="info-important">
|
|
|
|
|
<p>This is an important post. It should extend the class ".info" and have its own CSS styles.</p>
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
<div class="info">
|
|
|
|
|
<p>This is a simple post. It has basic styling and can be extended for other uses.</p>
|
|
|
|
|
</div>
|
|
|
|
|
|
2018-10-10 18:03:03 -04:00
|
|
|
|
```
|
2020-08-13 17:24:35 +02:00
|
|
|
|
|
2020-09-07 16:11:08 +08:00
|
|
|
|
</section>
|