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HTML

CSS

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JavaScript

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HTML

              
                <div class="content">
  <p class="p">CSS 否定伪类选择器 <em>:not(X)</em>,是以一个简单的以选择器 `X` 为参数的功能性标记函数,将从匹配的元素集合中排除选择器 `X` 所匹配的元素。选择器 `X` 中不能包含另外一个 <em>:not()</em> 选择器。</p>

  <div class="notice"><em>:not()</em> 伪类可以将一个或多个以逗号分隔的选择器作为其参数。但是以多个以逗号分隔的选择器作为参数是实验性的,尚未广泛支持。</div>

  <p class="p"><em>:not()</em> 伪类时我们得选择器组合更加灵活,我们来看一些简单的应用</p>
</div>
              
            
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CSS

              
                .content :not(.notice) em{
  color:red
}
.content .notice{ 
     background: #ffe7e8;
    border-left: 4px #e66465 solid;
  padding:10px;
}
              
            
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JS

              
                
              
            
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999px

Console