html - :before and :after pseudo-elements? 的默认显示属性是什么

Question

在您指定内容之后，:AFTER 和:BEFORE 伪元素的默认display: 属性是什么。

是display: inline还是display: inline-block？

无法在 default css values list 中找到它

例子:

div {
  border: solid 1px black;
  padding: 5px;
  }

div:before {
  content: "Before: Am I inline-block or inline?";
  color:red;
 }

div:after {
  content: "After: Am I Inline-block or inline?";
  color:green;
 }

<div>Div 1</div>
<div>Div 2</div>
<div>Div 3</div>
<div>Div 4</div>

Answer 1

:before 和:after 伪元素是inline by default .

作为W3 spec说:

In a :before or :after pseudo-element declaration, non-inherited properties take their initial values.

还有 initial value of the display property是内联的。