拉伸链接
通过 CSS“拉伸”嵌套链接，使任何 HTML 元素或 Bootstrap 组件可点击。
在链接中添加 .stretched-link 可以通过 ::after 伪元素使其包含块可点击。在大多数情况下，这意味着包含一个带有 .stretched-link 类链接的具有 position: relative; 的元素是可点击的。请注意，鉴于 CSS position 的工作原理，.stretched-link 不能与大多数表格元素混合使用。
🌐 Add .stretched-link to a link to make its containing block clickable via a ::after pseudo element. In most cases, this means that an element with position: relative; that contains a link with the .stretched-link class is clickable. Please note given how CSS position works, .stretched-link cannot be mixed with most table elements.
在 Bootstrap 中，卡片默认具有 position: relative，所以在这种情况下，你可以安全地将 .stretched-link 类添加到卡片中的链接，而无需进行任何其他 HTML 更改。
🌐 Cards have position: relative by default in Bootstrap, so in this case you can safely add the .stretched-link class to a link in the card without any other HTML changes.
不推荐在拉伸的链接中使用多个链接和点击目标。不过，如果有需要，一些 position 和 z-index 样式可以有所帮助。
🌐 Multiple links and tap targets are not recommended with stretched links. However, some position and z-index styles can help should this be required.
Card with stretched link
Some quick example text to build on the card title and make up the bulk of the card’s content.
Go somewhere<div class="card" style="width: 18rem;">
<img src="..." class="card-img-top" alt="...">
<div class="card-body">
<h5 class="card-title">Card with stretched link</h5>
<p class="card-text">Some quick example text to build on the card title and make up the bulk of the card’s content.</p>
<a href="#" class="btn btn-primary stretched-link">Go somewhere</a>
</div>
</div>大多数自定义组件默认没有 position: relative，所以我们需要在这里添加 .position-relative 来防止链接超出父元素。
🌐 Most custom components do not have position: relative by default, so we need to add the .position-relative here to prevent the link from stretching outside the parent element.
Custom component with stretched link
This is some placeholder content for the custom component. It is intended to mimic what some real-world content would look like, and we’re using it here to give the component a bit of body and size.
Go somewhere<div class="d-flex position-relative">
<img src="..." class="flex-shrink-0 me-3" alt="...">
<div>
<h5 class="mt-0">Custom component with stretched link</h5>
<p>This is some placeholder content for the custom component. It is intended to mimic what some real-world content would look like, and we’re using it here to give the component a bit of body and size.</p>
<a href="#" class="stretched-link">Go somewhere</a>
</div>
</div>Columns with stretched link
Another instance of placeholder content for this other custom component. It is intended to mimic what some real-world content would look like, and we’re using it here to give the component a bit of body and size.
Go somewhere<div class="row g-0 bg-body-secondary position-relative">
<div class="col-md-6 mb-md-0 p-md-4">
<img src="..." class="w-100" alt="...">
</div>
<div class="col-md-6 p-4 ps-md-0">
<h5 class="mt-0">Columns with stretched link</h5>
<p>Another instance of placeholder content for this other custom component. It is intended to mimic what some real-world content would look like, and we’re using it here to give the component a bit of body and size.</p>
<a href="#" class="stretched-link">Go somewhere</a>
</div>
</div>识别包含块
🌐 Identifying the containing block
如果拉伸的链接似乎不起作用，包含块可能是原因。以下 CSS 属性会使一个元素成为包含块：
🌐 If the stretched link doesn’t seem to work, the containing block will probably be the cause. The following CSS properties will make an element the containing block:
- 一个不是
static的position值 - 除
none外的transform或perspective值 will-change的值为transform或perspectivefilter值不是none或will-change值为filter（仅在 Firefox 上有效）
Card with stretched links
Some quick example text to build on the card title and make up the bulk of the card’s content.
Stretched link will not work here, because position: relative is added to the link
This stretched link will only be spread over the p-tag, because a transform is applied to it.
<div class="card" style="width: 18rem;">
<img src="..." class="card-img-top" alt="...">
<div class="card-body">
<h5 class="card-title">Card with stretched links</h5>
<p class="card-text">Some quick example text to build on the card title and make up the bulk of the card’s content.</p>
<p class="card-text">
<a href="#" class="stretched-link text-danger" style="position: relative;">Stretched link will not work here, because <code>position: relative</code> is added to the link</a>
</p>
<p class="card-text bg-body-tertiary" style="transform: rotate(0);">
This <a href="#" class="text-warning stretched-link">stretched link</a> will only be spread over the <code>p</code>-tag, because a transform is applied to it.
</p>
</div>
</div>