* 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>
7.0 KiB
7.0 KiB
id, title, challengeType, videoUrl, forumTopicId, dashedName
id | title | challengeType | videoUrl | forumTopicId | dashedName |
---|---|---|---|---|---|
587d778d367417b2b2512aaa | 使用自定义 CSS 让元素仅对屏幕阅读器可见 | 0 | https://scrimba.com/c/cJ8QGkhJ | 301020 | make-elements-only-visible-to-a-screen-reader-by-using-custom-css |
--description--
到目前为止,所有关于可访问性的挑战都没有使用 CSS。这是为了让你在关注外观样式之前,先把页面的逻辑结构写清,以及明确语义化标签的重要性。
但如果我们想在页面中添加一些只对屏幕阅读器可见的内容,此时我们可以用 CSS 来实现。当信息以可视化形式(比如图表)展示,而屏幕阅读器用户需要另一种方式(比如表格)来获取信息时,我们就可以用 CSS 来解决这个问题:只需要把仅供屏幕阅读器使用的信息通过 CSS 定位到浏览器可见区域之外即可。
举个例子:
.sr-only {
position: absolute;
left: -10000px;
width: 1px;
height: 1px;
top: auto;
overflow: hidden;
}
**注意:**以下的 CSS 解决方案与上面的结果不同:
display: none;
或visibility: hidden;
会把内容彻底隐藏起来,屏幕阅读器也无法获取这些内容。- 如果把值设置为 0px,如
width: 0px; height: 0px;
,意味着让元素脱离文档流,这样做同样也会让屏幕阅读器忽略此元素。
--instructions--
Camper Cat 为他的训练页面创建了一个十分酷炫的条形图。考虑到可访问性,他还将数据放入到了一个表格中,供屏幕阅读器用户使用。表格的 class
为 sr-only
,但是还没有添加 CSS 规则。请将 position
的值设置为 absolute、left
的值设置为 -10000px、width
与 height
的值均设置为 1px。
--hints--
class
为 sr-only
的元素的 position
属性值应为 absolute。
assert($('.sr-only').css('position') == 'absolute');
class
为 sr-only
的元素的 left
属性值应为 -10000px。
assert($('.sr-only').css('left') == '-10000px');
class
为 sr-only
的元素的 width
属性值应为 1px。
assert(code.match(/width:\s*?1px/gi));
class
为 sr-only
的元素的 height
属性值应为 1px。
assert(code.match(/height:\s*?1px/gi));
--seed--
--seed-contents--
<head>
<style>
.sr-only {
position: ;
left: ;
width: ;
height: ;
top: auto;
overflow: hidden;
}
</style>
</head>
<body>
<header>
<h1>Training</h1>
<nav>
<ul>
<li><a href="#stealth">Stealth & Agility</a></li>
<li><a href="#combat">Combat</a></li>
<li><a href="#weapons">Weapons</a></li>
</ul>
</nav>
</header>
<section>
<h2>Master Camper Cat's Beginner Three Week Training Program</h2>
<figure>
<!-- Stacked bar chart of weekly training -->
<p>[Stacked bar chart]</p>
<br />
<figcaption>Breakdown per week of time to spend training in stealth, combat, and weapons.</figcaption>
</figure>
<table class="sr-only">
<caption>Hours of Weekly Training in Stealth, Combat, and Weapons</caption>
<thead>
<tr>
<th></th>
<th scope="col">Stealth & Agility</th>
<th scope="col">Combat</th>
<th scope="col">Weapons</th>
<th scope="col">Total</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">Week One</th>
<td>3</td>
<td>5</td>
<td>2</td>
<td>10</td>
</tr>
<tr>
<th scope="row">Week Two</th>
<td>4</td>
<td>5</td>
<td>3</td>
<td>12</td>
</tr>
<tr>
<th scope="row">Week Three</th>
<td>4</td>
<td>6</td>
<td>3</td>
<td>13</td>
</tr>
</tbody>
</table>
</section>
<section id="stealth">
<h2>Stealth & Agility Training</h2>
<article><h3>Climb foliage quickly using a minimum spanning tree approach</h3></article>
<article><h3>No training is NP-complete without parkour</h3></article>
</section>
<section id="combat">
<h2>Combat Training</h2>
<article><h3>Dispatch multiple enemies with multithreaded tactics</h3></article>
<article><h3>Goodbye, world: 5 proven ways to knock out an opponent</h3></article>
</section>
<section id="weapons">
<h2>Weapons Training</h2>
<article><h3>Swords: the best tool to literally divide and conquer</h3></article>
<article><h3>Breadth-first or depth-first in multi-weapon training?</h3></article>
</section>
<footer>© 2018 Camper Cat</footer>
</body>
--solutions--
<head>
<style>
.sr-only {
position: absolute;
left: -10000px;
width: 1px;
height: 1px;
top: auto;
overflow: hidden;
}
</style>
</head>
<body>
<header>
<h1>Training</h1>
<nav>
<ul>
<li><a href="#stealth">Stealth & Agility</a></li>
<li><a href="#combat">Combat</a></li>
<li><a href="#weapons">Weapons</a></li>
</ul>
</nav>
</header>
<section>
<h2>Master Camper Cat's Beginner Three Week Training Program</h2>
<figure>
<!-- Stacked bar chart of weekly training -->
<p>[Stacked bar chart]</p>
<br />
<figcaption>Breakdown per week of time to spend training in stealth, combat, and weapons.</figcaption>
</figure>
<table class="sr-only">
<caption>Hours of Weekly Training in Stealth, Combat, and Weapons</caption>
<thead>
<tr>
<th></th>
<th scope="col">Stealth & Agility</th>
<th scope="col">Combat</th>
<th scope="col">Weapons</th>
<th scope="col">Total</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">Week One</th>
<td>3</td>
<td>5</td>
<td>2</td>
<td>10</td>
</tr>
<tr>
<th scope="row">Week Two</th>
<td>4</td>
<td>5</td>
<td>3</td>
<td>12</td>
</tr>
<tr>
<th scope="row">Week Three</th>
<td>4</td>
<td>6</td>
<td>3</td>
<td>13</td>
</tr>
</tbody>
</table>
</section>
<section id="stealth">
<h2>Stealth & Agility Training</h2>
<article><h3>Climb foliage quickly using a minimum spanning tree approach</h3></article>
<article><h3>No training is NP-complete without parkour</h3></article>
</section>
<section id="combat">
<h2>Combat Training</h2>
<article><h3>Dispatch multiple enemies with multithreaded tactics</h3></article>
<article><h3>Goodbye, world: 5 proven ways to knock out an opponent</h3></article>
</section>
<section id="weapons">
<h2>Weapons Training</h2>
<article><h3>Swords: the best tool to literally divide and conquer</h3></article>
<article><h3>Breadth-first or depth-first in multi-weapon training?</h3></article>
</section>
<footer>© 2018 Camper Cat</footer>
</body>