css - 使用 CSS 更改带有嵌套输入字段的字段集的背景颜色

Question

我正在使用这个解决方案: Is it possible to change a fieldset's background-color on input:focus?

... 当用户在表单中移动时更改字段集的背景。在基本层面上，这很好用。在更高级的级别上，我无法在嵌套在条件 div 内的输入字段上进行这项工作。换句话说，在他的示例中，输入不再是 div 的兄弟。

给你一个视觉效果，这是可行的:

<fieldset>
<input>
<div></div>
</fieldset>

但这不是:

<fieldset> 
<div class="conditional"> 
<input> 
</div> 
<div></div> 
</fieldset>

Answer 1

实际上，您现在可以通过

影响焦点输入的父级

:focus-within

The :focus-within CSS pseudo-class represents an element that has received focus or contains an element that has received focus. In other words, it represents an element that is itself matched by the :focus pseudo-class or has a descendant that is matched by :focus. (This includes descendants in shadow trees.)

MDN

fieldset:focus-within {
  background: red;
}

<fieldset>
  <input>
</fieldset>