freeCodeCamp/curriculum/challenges/english/01-responsive-web-design/basic-css/use-css-selectors-to-style-...

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---
id: bad87fee1348bd9aedf08805
title: Use CSS Selectors to Style Elements
challengeType: 0
videoUrl: 'https://scrimba.com/c/cJKMBT2'
---
## Description
<section id='description'>
With CSS, there are hundreds of CSS <code>properties</code> that you can use to change the way an element looks on your page.
When you entered <code>&#60;h2 style="color: red"&#62;CatPhotoApp&#60;/h2&#62;</code>, you were styling that individual <code>h2</code> element with <code>inline CSS</code>, which stands for <code>Cascading Style Sheets</code>.
That's one way to specify the style of an element, but there's a better way to apply <code>CSS</code>.
At the top of your code, create a <code>style</code> block like this:
<blockquote>&#60;style&#62;<br>&#60;/style&#62;</blockquote>
Inside that style block, you can create a <code>CSS selector</code> for all <code>h2</code> elements. For example, if you wanted all <code>h2</code> elements to be red, you would add a style rule that looks like this:
<blockquote>&#60;style&#62;<br>&nbsp;&nbsp;h2 {color: red;}<br>&#60;/style&#62;</blockquote>
Note that it's important to have both opening and closing curly braces (<code>{</code> and <code>}</code>) around each element's style rule(s). You also need to make sure that your element's style definition is between the opening and closing style tags. Finally, be sure to add a semicolon to the end of each of your element's style rules.
</section>
## Instructions
<section id='instructions'>
Delete your <code>h2</code> element's style attribute, and instead create a CSS <code>style</code> block. Add the necessary CSS to turn all <code>h2</code> elements blue.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: Remove the style attribute from your <code>h2</code> element.
testString: 'assert(!$("h2").attr("style"), "Remove the style attribute from your <code>h2</code> element.");'
- text: Create a <code>style</code> element.
testString: 'assert($("style") && $("style").length > 1, "Create a <code>style</code> element.");'
- text: Your <code>h2</code> element should be blue.
testString: 'assert($("h2").css("color") === "rgb(0, 0, 255)", "Your <code>h2</code> element should be blue.");'
- text: Ensure that your stylesheet <code>h2</code> declaration is valid with a semicolon and closing brace.
testString: 'assert(code.match(/h2\s*\{\s*color\s*:.*;\s*\}/g), "Ensure that your stylesheet <code>h2</code> declaration is valid with a semicolon and closing brace.");'
- text: Make sure all your <code>style</code> elements are valid and have a closing tag.
testString: 'assert(code.match(/<\/style>/g) && code.match(/<\/style>/g).length === (code.match(/<style((\s)*((type|media|scoped|title|disabled)="[^"]*")?(\s)*)*>/g) || []).length, "Make sure all your <code>style</code> elements are valid and have a closing tag.");'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='html-seed'>
```html
<h2 style="color: red">CatPhotoApp</h2>
<main>
<p>Click here to view more <a href="#">cat photos</a>.</p>
<a href="#"><img src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
<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>
</div>
<form action="/submit-cat-photo">
<label><input type="radio" name="indoor-outdoor" checked> Indoor</label>
<label><input type="radio" name="indoor-outdoor"> Outdoor</label><br>
<label><input type="checkbox" name="personality" checked> Loving</label>
<label><input type="checkbox" name="personality"> Lazy</label>
<label><input type="checkbox" name="personality"> Energetic</label><br>
<input type="text" placeholder="cat photo URL" required>
<button type="submit">Submit</button>
</form>
</main>
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>