freeCodeCamp/curriculum/challenges/english/01-responsive-web-design/basic-css/use-a-media-query-to-change-a-variable.md
Oliver Eyton-Williams ee1e8abd87
feat(curriculum): restore seed + solution to Chinese (#40683)
* feat(tools): add seed/solution restore script

* chore(curriculum): remove empty sections' markers

* chore(curriculum): add seed + solution to Chinese

* chore: remove old formatter

* fix: update getChallenges

parse translated challenges separately, without reference to the source

* chore(curriculum): add dashedName to English

* chore(curriculum): add dashedName to Chinese

* refactor: remove unused challenge property 'name'

* fix: relax dashedName requirement

* fix: stray tag

Remove stray `pre` tag from challenge file.

Signed-off-by: nhcarrigan <nhcarrigan@gmail.com>

Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
2021-01-12 19:31:00 -07:00

282 lines
5.5 KiB
Markdown

---
id: 5a9d72ad424fe3d0e10cad16
title: Use a media query to change a variable
challengeType: 0
videoUrl: 'https://scrimba.com/c/cWmL8UP'
forumTopicId: 301091
dashedName: use-a-media-query-to-change-a-variable
---
# --description--
CSS Variables can simplify the way you use media queries.
For instance, when your screen is smaller or larger than your media query break point, you can change the value of a variable, and it will apply its style wherever it is used.
# --instructions--
In the `:root` selector of the `media query`, change it so `--penguin-size` is redefined and given a value of `200px`. Also, redefine `--penguin-skin` and give it a value of `black`. Then resize the preview to see this change in action.
# --hints--
`:root` should reassign the `--penguin-size` variable to `200px`.
```js
assert(
code.match(
/media\s*?\(\s*?max-width\s*?:\s*?350px\s*?\)\s*?{[\s\S]*:root\s*?{[\s\S]*--penguin-size\s*?:\s*?200px\s*?;[\s\S]*}[\s\S]*}/gi
)
);
```
`:root` should reassign the `--penguin-skin` variable to `black`.
```js
assert(
code.match(
/media\s*?\(\s*?max-width\s*?:\s*?350px\s*?\)\s*?{[\s\S]*:root\s*?{[\s\S]*--penguin-skin\s*?:\s*?black\s*?;[\s\S]*}[\s\S]*}/gi
)
);
```
# --seed--
## --seed-contents--
```html
<style>
:root {
--penguin-size: 300px;
--penguin-skin: gray;
--penguin-belly: white;
--penguin-beak: orange;
}
@media (max-width: 350px) {
:root {
/* Only change code below this line */
/* Only change code above this line */
}
}
.penguin {
position: relative;
margin: auto;
display: block;
margin-top: 5%;
width: var(--penguin-size, 300px);
height: var(--penguin-size, 300px);
}
.right-cheek {
top: 15%;
left: 35%;
background: var(--penguin-belly, white);
width: 60%;
height: 70%;
border-radius: 70% 70% 60% 60%;
}
.left-cheek {
top: 15%;
left: 5%;
background: var(--penguin-belly, white);
width: 60%;
height: 70%;
border-radius: 70% 70% 60% 60%;
}
.belly {
top: 60%;
left: 2.5%;
background: var(--penguin-belly, white);
width: 95%;
height: 100%;
border-radius: 120% 120% 100% 100%;
}
.penguin-top {
top: 10%;
left: 25%;
background: var(--penguin-skin, gray);
width: 50%;
height: 45%;
border-radius: 70% 70% 60% 60%;
}
.penguin-bottom {
top: 40%;
left: 23.5%;
background: var(--penguin-skin, gray);
width: 53%;
height: 45%;
border-radius: 70% 70% 100% 100%;
}
.right-hand {
top: 5%;
left: 25%;
background: var(--penguin-skin, black);
width: 30%;
height: 60%;
border-radius: 30% 30% 120% 30%;
transform: rotate(130deg);
z-index: -1;
animation-duration: 3s;
animation-name: wave;
animation-iteration-count: infinite;
transform-origin:0% 0%;
animation-timing-function: linear;
}
@keyframes wave {
10% {
transform: rotate(110deg);
}
20% {
transform: rotate(130deg);
}
30% {
transform: rotate(110deg);
}
40% {
transform: rotate(130deg);
}
}
.left-hand {
top: 0%;
left: 75%;
background: var(--penguin-skin, gray);
width: 30%;
height: 60%;
border-radius: 30% 30% 30% 120%;
transform: rotate(-45deg);
z-index: -1;
}
.right-feet {
top: 85%;
left: 60%;
background: var(--penguin-beak, orange);
width: 15%;
height: 30%;
border-radius: 50% 50% 50% 50%;
transform: rotate(-80deg);
z-index: -2222;
}
.left-feet {
top: 85%;
left: 25%;
background: var(--penguin-beak, orange);
width: 15%;
height: 30%;
border-radius: 50% 50% 50% 50%;
transform: rotate(80deg);
z-index: -2222;
}
.right-eye {
top: 45%;
left: 60%;
background: black;
width: 15%;
height: 17%;
border-radius: 50%;
}
.left-eye {
top: 45%;
left: 25%;
background: black;
width: 15%;
height: 17%;
border-radius: 50%;
}
.sparkle {
top: 25%;
left:-23%;
background: white;
width: 150%;
height: 100%;
border-radius: 50%;
}
.blush-right {
top: 65%;
left: 15%;
background: pink;
width: 15%;
height: 10%;
border-radius: 50%;
}
.blush-left {
top: 65%;
left: 70%;
background: pink;
width: 15%;
height: 10%;
border-radius: 50%;
}
.beak-top {
top: 60%;
left: 40%;
background: var(--penguin-beak, orange);
width: 20%;
height: 10%;
border-radius: 50%;
}
.beak-bottom {
top: 65%;
left: 42%;
background: var(--penguin-beak, orange);
width: 16%;
height: 10%;
border-radius: 50%;
}
body {
background:#c6faf1;
}
.penguin * {
position: absolute;
}
</style>
<div class="penguin">
<div class="penguin-bottom">
<div class="right-hand"></div>
<div class="left-hand"></div>
<div class="right-feet"></div>
<div class="left-feet"></div>
</div>
<div class="penguin-top">
<div class="right-cheek"></div>
<div class="left-cheek"></div>
<div class="belly"></div>
<div class="right-eye">
<div class="sparkle"></div>
</div>
<div class="left-eye">
<div class="sparkle"></div>
</div>
<div class="blush-right"></div>
<div class="blush-left"></div>
<div class="beak-top"></div>
<div class="beak-bottom"></div>
</div>
</div>
```
# --solutions--
```html
<style>@media (max-width: 350px) {:root {--penguin-size: 200px; --penguin-skin: black;}}</style>
```